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GULLIVER v5.3 (2004.04.12) | Copyright 2004 T.Bone | T.Bone's GURPS Diner

Book 3: The Body Shop

Add-ons and Options for Creatures in GURPS


This Book adds three things to the many creature design toys already in GURPS:

The below looks at options as grouped "subsystems" – frame, respiration, hide, legs, and so on. Choosing from these groups is more fun than going through alphabetical lists of unrelated traits.

Two big things that GURPS leaves untouched in its design rules are size and power-to-weight issues. These are covered thoroughly in Book 1 and Book 2. Book 3 notes where size and weight would affect the workings of other traits, but most of it can be used without the previous Books.

There's a lot more GULLIVER content that could have gone into Book 3: notes on creature design practices, a nifty list of "skill bonus traits" representing common talents, a flexible and precise Appendage Builder System, and a spiffy Life Span Meta-system. As this Book is already bursting at the seems, this content is placed in Book X.

Notes on Traits

Traits are advantages, disadvantages, and more – everything and anything that define a character. Some concepts used throughout GULLIVER:

Package Traits

Package Traits are those combining several other traits, such as Amorphous Body below. Cost is only that of the component traits you choose.

The Rule of -5

Many traits below come in levels, but too many levels of a disadvantage is abusive. (If three levels will get you killed, ten levels won't get you killed any deader.) A "Rule of -5" is applied to such traits: you can take a maximum of five levels, and sometimes that fifth level heaps all-new troubles onto the existing woes!

Using Limitations and Enhancements

Additive limitations

Many traits can take percentage limitations and enhancements, such as "-20%". Those are additive, not multiplicative, in GURPS – which isn't always a good thing, but that's the rule.

Limits on limitations

GULLIVER raises GURPS' -75% limit on limitations to -80%. That leaves a neat integer for the many traits whose base cost is divisible by 5, and meshes with several rules that use traits reduced to one-fifth cost.

Use the -80% limit when an advantage offers some net benefit despite its limitations. An arm that's weak and short is still an advantage if it happens to be a third arm.

Use a -100% limit when all benefit disappears from an advantage. For example, No Manual DX and No Grip are -50% limitations on the cost of your manipulators that do add up to -100%, or 0, cost. Combined, they completely remove the ability to manipulate.

Multiplicative limitations

Limitations in the form of "x3/4" instead of "-25%", and enhancements in the form of "x1.5", sometimes work better. They appear in spots (including in GURPS' modifiers for the cost of Reputation, Enemies, Weakness, psionic powers in older books, etc.).

Overlapping Disadvantages

Like limitations, disadvantages can add up to too much: it's possible to total up vision-related disadvantages that exceed the value of Blindness, or movement-related ones that exceed the value of Sessile.

A technical solution is to treat sight as a 50-point advantage, and decrease its value with multiplicative limitations like Bad Sight [x1/2], Color Blindness [x4/5], etc. But that's too big an overhaul of the rules.

The best fix is to disallow disadvantages that don't hamper the character, or whose effects are clearly covered by another trait. Use common sense and be strict.

When you do want multiple disadvantages to take effect, yet without overdone point values, here's GULLIVER's overlapping disadvantage rule:

Reduce the value of disadvantages whose effects overlap. Use the largest disadvantage as is, multiply the cost of the next largest by x1/2, the next largest by x1/4, the next by x1/8, etc.

Total disadvantage value is limited to -80% of the worse possible disadvantage if any ability remains, or -100% if all ability is removed.

Treat a leveled disadvantage as a single disadvantage.

Example: Combined nearsightedness [-25] and farsightedness [-25 x 1/2 = 12.5] is worth -37.5 points. Adding Colorblindness [-10 x 1/4 = 2.5] brings that to -40 points. Blindness [-50] is the worst vision you can have, so -40 points [-50 x 80% = -40] is the limit for lesser vision defects.

Example: One Leg [-30], 5 levels of Reduced Move [-25 x1/2] and the inability to run backward [-12 x1/4] total -45.5 points. However, Sessile [-50] represents a worst-case scenario, so limit the total value of the above lesser disadvantages to 80% of Sessile's value, or -40 points.

Example: Impulsiveness and Overconfidence overlap a lot; either one will get the PC into many of the same scrapes as the other. Reduce the combination to -15 points. (This may affect many existing PC designs!)

Creatures, Points, and Detail

Fair, balanced point costs can be tricky; their details take up a lot of the space below. Fortunately, if you're not designing a PC race, points don't matter. Choose your design's traits and skip any discussion of points.

A non-PC may not even need a detailed listing of traits. A monster for gratuitous combat can do without non-combat traits. Non-threatening creatures may not need stats at all – they're just story elements that provide food or haul PCs' treasure.

On the other hand, designs for PCs and major NPCs should be detailed enough that capabilities are clear before play. But there will always be gray areas in a complex design. Don't worry much about getting every cost "correct"; if total points in question amount to 10% or less of the character total, you did well. Put down the pencil and play.

The GURPS Default Creature

The "default" creature in most games is a human, or at least a creature with humanlike characteristics. A creature can be very un-humanlike yet still have no point cost, if its body has human capabilities!

Start with this default and modify as you go through the list below. Skip whatever you can't decide on or aren't interested in, returning later if you want.

The Big Questions

If you know your design's role in the game, its environment, and whether or not it hews to reality, you'll breeze through the design process.

Creature Role

The most important decision you'll make is: What's your creature for? A PC or NPC race, a PC-eating menace, a beast of burden for the PCs, what? (There's a reason "PC" appeared so many times in that sentence: what's important is your design's role in relation to the player characters.)

Here are some buzzwords to spur imagination:

Creature Role options: PC race; NPC race; companion; work beast; food/prey; nuisance; local color; minor menace; major menace; extreme menace; menace if provoked; etc.

Reality Level

Related to role is reality level – does (or could) your creature exist on Earth? In a "hard" science fiction novel? Space opera or high fantasy only? What fantastic abilities will you allow?

Reality Level options: Earth-real; hard sci-fi/low fantasy; space opera/high fantasy.


Is your design a species, mutant, hybrid, or unique being?

Mutants and hybrids may have traits that a species would have never developed. Realistic ones might be weak – blind or sterile, even. A more fun mutant is one so powerful and prolific that it'd take over the world if it were a species. (Read: adventure plot!)

A unique being might sport any traits you can think of. (Hobbits can't see in the dark, but the ex-Hobbit Gollum could.) This can be a one-of-a-kind creature, or an individual member of a species (such as an individual dragon). Unique designs are fun for the GM to play and provide surprises for the PCs.

Uniqueness options: species; non-species (mutant, hybrid or unique).

Environment & Habitat

Characters can hail from an infinite variety of environments, but for game purposes, three main Environments (capitalized!) are important: land, water, and air. (GULLIVER will use the word "habitat" to mean more specific surroundings.)

Home Environments

You can feel at home in more than just one Environment: Amphibious makes you equally comfortable in both land and water, and flight traits add air to the mix. Environments in which you can operate comfortably are your home Environments, whether those be one, two, or all three.

Primary Environment

If you have more than one home Environment, pick one as your primary Environment. Choose the one you're most mobile in. If you're equally mobile in two or more, pick the one that will host the most game action (usually land).

Your primary Environment is the same as your primary mode of movement – land, water or air. (Other words to describe you based on this choice are terrestrial, aquatic, and aerial.)

Primary Environment and Trait Costs

Here's a point crock you may have noticed. In GURPS, a character with Amphibious [10] and four or five levels of Reduced Move (water) [-20 or -25] retains a better aquatic Move than landbound PCs, yet doesn't need to make Swimming rolls, and nabs a free 10 or 15 net points in the process!

The problem is that GURPS awards full points for environmentally-related disadvantages, whether the PC actually "belongs to" the environment in question or not. The fix: disadvantages that only affect you in a non-primary Environment should be worth little. (Make that nothing if they're completely irrelevant, like Reduced Move (air) for a non-flier.)

Adjust trait costs for Environment as follows:

Advantages that affect you in only one Environment

Enhanced Move is an example. Buy the advantage separately for each Environment, at full cost.

Disadvantages that affect you in only one Environment

Reduced Move is an example. You can take the trait separately for each Environment – but at full cost only for your primary one. Otherwise, cut disadvantage value to x1/5.

Advantages that affect you in all Environments

Negative encumbrance is an example: one purchase affects you in air, water, or on land.

Reduce cost to x1/2 if the advantage only affects you in one non-primary Environment (say, water if you're terrestrial), or to x2/3 for two non-primary ones.

If the advantage only affects you in your primary Environment, there's little point break: reduce the cost to x4/5.

Disadvantages that affect you in all Environments

Reduced Dodge is an example: one purchase affects you in all Environments. Cut the value to x1/5 if the disadvantage only affects you in a non-primary Environment, x2/5 for two. Cut it to x1/2 if it only affects you in your primary one (or x1/3 if you have two non-primary Environments to fall back on).

Example: You have Amphibious. With both land and water as choices, you pick land as your primary Environment. You're terrestrial, with added water mobility from Amphibious. If you're a slow swimmer, levels of Reduced Move (water) are worth only -5 x 1/5 = -1 point each – no point crock here!

Example: Again you build a PC at home in land and water, but label this one aquatic, with land mobility added by Amphibious.

If you're a slow swimmer, levels of Reduced Move (water) are worth a full -5 points each. If you're also slow on dry earth, add Reduced Move (land) – but those levels are going to be worth a measly -1 point each.

Example: Your aquatic PC's eyes are nearsighted on land. Bad Sight normally affects you everywhere for -25 points. But here it affects you only in on land, which isn't your primary Environment. It's worth one-fifth value, or -5 points.

Flight and primary Environment

Flight assumes a terrestrial (or rarely, aquatic) creature with the added mode of air, so air won't normally be your primary Environment. All air-only disadvantages, such as Reduced Move (air), will have one-fifth their value for you.

Allow two exceptions:

One: If you're a very competent flier, you can pretty much do anything a terrestrial creature can do – and more, all without touching the ground. You could take lots of points for disadvantages like Lame, Reduced Move (land), No Jump, etc., yet they'll rarely slow you down at all.

For that reason, a creature which is a very competent flier should make air its primary Environment, meaning non-air disadvantages will net it very few points. "Very competent" here is a GM call; 45 or more points in Flight, levitation powers, etc. might suffice.

Two: A "floater" at home nowhere but in its atmospheric environment is truly aerial. Buy powerful flight abilities and call air your primary Environment. (The Grapple Bird from Space Bestiary p. 7 seems to be a true aerial creature, with added water mobility from Amphibious but no land mobility.)

Primary Environment and Default Abilities

Below are the effects of each primary Environment in game terms. See Book 4 for actual calculation of Move, as well as Reduced Move below.


0 points

Your primary Environment is land, where you have normal physical capabilities. Water is a different story.

You have 5 levels of Reduced Move (water), worth only -5 points for a non-aquatic creature. That cuts your water Move to x1/10.

You also have a disadvantage that could be named Unadapted (water), also worth -5 points to you. Unlike a fish, you suffer physical action penalties in water and risk drowning. In general, take a -2 on active defenses and other abilities. You even need a special Physical/Easy skill just to get around: Swimming skill.

These disadvantages are the 0-point default condition for a landlubber. Buy them off with Amphibious. Or buy them off partially: first buy off Unadapted (water) for 5 points, and then levels of Reduced Move (water) a point at a time. (This is the same as first buying Amphibious and adding levels of Reduced Move (water)).


0 points

Your primary Environment is water, where you have normal physical capabilities. On dry land you're a fish out of water.

You have 5 levels of Reduced Move (land), worth only -5 points for a non-terrestrial creature. That cuts your land Move to x1/10.

You also have a disadvantage that could be named Unadapted (land), also worth -5 points to you. You're not built for moving on the ground. Climbing, jumping, and so on are generally out of the question. Getting around is a difficult process requiring a special Physical/Easy skill, either Crawling or Flopping (see Book 4).

You also suffer penalties on combat and other physical actions on land. In general, take a -2 on active defenses and other abilities. Don't forget penalties for natural encumbrance! If you're too heavy on land to move at all, then no movement skills are going to help you – you're beached.

These disadvantages are your 0-point default condition. Buy them off with Amphibious. Or buy them off partially: first buy off Unadapted (land) for 5 points, and then levels of Reduced Move (land) a point at a time. (This is the same as buying Amphibious and adding levels of Reduced Move (land)).


-10 points + flight traits

Your primary mode of movement is air; you're a true "floater". Buy some form of gliding, powered flight, buoyancy, etc. at normal cost as your primary mode of movement. You gain the appropriate physical capabilities in the air.

The -10 point base covers the land haplessness of an aquatic creature and the water clumsiness of a terrestrial creature. Buy back water mobility with Amphibious [10], and buy back land mobility with an analogous ability that floaters might call "Landwalking" [10].


You'll want to get a little more specific than just "land" or "water". GURPS Bestiary offers a list of Earth habitats including Aquatic Fresh-Water, Aquatic Salt-Water, Arctic, Desert, Forest, Jungle, Mountain, Plains, Subterranean, and Swamp.

Here are a few more, Earthly and otherwise:

Mixed habitats

Multiple habitats are fine too; look at the ranges occupied by go-anywhere, eat-anything vermin like rats, roaches, and humans.

A combined habitat, on the other hand, is restricting: say, Jungle and Mountain, as opposed to Jungle or Mountain. Combined habitats often have a specific name. A taiga combines Arctic and Forest; a tundra combines features of Arctic and Plains with the precipitation of Desert.

Specific habitats

There's a lot of variation to be found in each category above. "Aquatic, Salt-Water" could be deep sea, open sea, shallows, or coral reef. "Aquatic, Fresh-Water" covers rivers, lakes, and ponds – all of which in turn range from open water to stands of reeds. "Plains" can be hot or cold. "Parasitic Host" needs gory detail. And "Urban, Subterranean" doesn't tell the whole story of ghouls – "catacombs, tombs, and sewers" is better.


Most adult creatures should have the Survival skill at some level – say, the higher of IQ and 12. Let this be free. (For modern, moneyed humans, little actual "survival" is involved; our free skill is one of shopping, career advancement, and choosing the cheapest long-distance phone carrier.)

Habitat specialization

The more specialized you are for a specific habitat, the better you do when snug in those surroundings. But when surroundings change, the specialists fall behind the generalists. Subtract 1 from base Survival skill per +3 for specialization.

Example: You can have Survival (Forest) at IQ. Or make that Survival (Forest) at IQ-1 and Survival (Deciduous Rain Forest) at IQ +3. Or even consider Survival (Forest) at IQ-2, Survival (Deciduous Rain Forest) at IQ+3, and Survival (Deciduous Rain Forest, Upper Canopy) at IQ +6.

Hostile Environments

You shouldn't get points for the troubles you suffer when you choose to go to environments that are unsafe for you. Exceptions may apply if the PCs are expected to travel to certain surroundings as part of the game. Planetbound, Space Sickness, and Timesickness are examples.

Use and value are a GM call, depending on the restricted environments' number and their importance to the game. (If food in some environment is the problem, see Restricted Diet.)

Make up appropriate effects for exposure to the restricted environment. The above traits, as well as Weakness and Vulnerability, make good guidelines, but can offer very high disadvantage values. A new set of quickie rules might run like this:

Environmental Intolerance (new)


You can not safely enter certain environments important to the game setting. Base cost is -5 to -15 points depending on the game importance of the environment, with a multiplier based on the interval between the loss of 1 HP: 1 second [x2], 10 seconds [x1.5], 1 minute [x1], 10 minutes [x3/4], 1 hour [x2/3], 6 hours [x1/2], 1 day [x1/3], 1 week [x1/4], 1 month [x1/5], 6 months [x1/10]. This damage does not heal while you're exposed to the environment!

Limitations: Halve value if HT rolls negate fresh damage. Halve value if damage is suffocation (which can kill you, but takes longer).

Halve value if you can acclimatize yourself to the new environment. Details are up to the GM, but with slow, careful conditioning (usually involving gradual exposure), you can remove or lessen the threat of further damage. However, you'll need to slowly acclimatize yourself back to your old environment!

Increase disadvantage value to add other effects (sickness, fatigue, etc.) to damage.

Example: Fish PCs might face intolerance to either fresh or salt water, worth a base -5 points, modified for frequency of damage. Some fish will have the ability to slowly acclimatize.

GURPS's Aquatic disadvantage is a special case of Environmental Intolerance: you're a water-dweller encased in a tank of liquid, presumably dragged around by your legged PC pals. Or possibly you're limited to cameo appearances in dockside encounters, with rare chances to shine in real aquatic adventures. The high point cost seems to reflect your being shut out of nearly all adventures.

Environment & Habitat options: Environment (land; water; air); general or specific habitat; Survival skill specializations; Environmental Intolerance; Aquatic.

Basic Body Structure

Start with the appropriate default characteristics. Set ST, DX, HT, and HP at 10 and adjust as you go.

Body Plan

How are you laid out? Humans are bilaterally symmetrical (more or less, with asymmetrical innards). Creatures can also be asymmetrical (allowing weird shapes and odd limb arrangements), radially symmetrical (jellyfish, Lovecraftian monster, or starfish), or amorphous (amoeba).

Exotic body plans include dissociated floating globules, "swarm" beings, and that nonsense favorite, "non-Euclidean geometry". Details are up to you.

None of these necessarily affects the character sheet, except for appropriate additions of Monstrous Appearance, Reduced Move, or whatever sounds right. (Another exotic form, No Physical Body, does have specific effects; floating brains should check out CI p. 83.)

Inconvenient Form

If body shape does make life difficult for you, use this disadvantage:

Inconvenient Form (new)


This is a catchall disadvantage for a physical form that hampers a PC, typically a body shape that is difficult to clothe or armor, cannot use tools easily, or has difficulty entering homes and vehicles.

Most instances should be worth -5 to -15 points. A body that can't wear armor might be worth -10 points in a standard "adventurers" setting, more in a combat-heavy infantry campaign. A Kaa might be able to armor its torso, but not its snaky lower half, for a -5-point Inconvenient Form.

Some existing traits, like Hunchback or No Physical Body, already contain a dose of Inconvenient Form; don't add it separately.

Hybrid forms

A "hybrid" mixture of two (or more?) creatures is a special effect; build with appropriate traits. A Merman or Satyr combines the "upper" and "lower" halves of different creatures, but without any unusual treatment of size, ST, HP, etc.

But some creatures' "halves" are of very different sizes, such as the typical fantasy Centaur. The "upper" half usually bears the head and manipulators, while the "lower" half has legs and supports the creature's weight.

Cost of Size: If the two halves have different levels of the Size advantage, average the cost of the two Sizes.

Add Inconvenient Size (or Inconvenient Form) as appropriate. Sustenance needs will be appropriate for the bigger section, or somewhat greater.

In combat, the Size of individual targets (legs, head, etc.) will be appropriate for the Size of the appropriate half. To target the creature overall, as with a long-range missile, use the Size of the larger half. To target a specific half, use the appropriate Size, minus 1 – but a miss by only one hits the other half.

Cost of ST: If the two halves have different ST scores, adjust the ST of one half. See notes on adjusting arm, manipulator, striker, wing, leg, jaw, and other ST. For a man-horse Centaur, purchase the ST of the upper half normally, and the additional ST (both Combat ST and Load ST) of the lower half with a Legs Only limitation [-50%], which boosts only leg power and the carrying ability of the back. That's all you need to do; there's no need to average the costs of the two halves' ST.

Cost of HP: If the two halves have different HP, average the cost of the two. (See Book 6 to play this split HP score.) Average the cost of split DR or Toughness as well.

Other stuff: Figure natural encumbrance from total weight and the Load ST of the load-bearing half. Purchase normally.

Both halves have vital organs that can be targeted. Otherwise, buy No Vulnerability: Vitals for the whole creature [5] or one half [3].

Play other quirks of split attributes appropriately. Just be sure that limbs, functionality, and so forth are fairly split between the two halves (not concentrated in the "big half", with the "small half" nothing more than a point sink), and things will work. See Book 7 for a treatment of the fantasy Centaur using these guidelines.


The amorphous body is found in nanomorphs, amoebae, and house-swallowing globs of goo:

Amorphous Body (new)

varies (package)

You're a blob. Compile the appropriate traits, mostly with those from flexibility traits, for a limited shapechanging ability. Also look at Invertebrate, Injury Tolerances, advantages from "Regeneration and Recovery", and fun stuff like Slime.

For the ability to extrude limbs, tails, etc., pay for your full complement of extruded goods, and give them all Retraction (below).

Add the ability to replace arms with legs (and vice versa) with a new advantage, Limb Extrusion [5]. Pay for all limbs as arms (no cheap arms from Extra Legs and Limb Extrusion!). The change takes two minutes per limb; halve this time for each +1 point spent on the ability. Also halve time with a skill roll (see Squishy).

Anything more complex than this requires dedicated shapeshifting rules.


How do you orient your body, especially when moving? GURPS offers upright, Semi-Upright, and Horizontal, but GULLIVER reworks posture.

Define postures for creatures as appropriate, with as much detail as you like. A Tyrannosaur's posture is upright and leaning far forward. A fish's posture is... well, fishy.

Any posture, including upright, semi-upright or horizontal, is itself is no net advantage or disadvantage. Call posture an uncapitalized 0-point trait.

In general, upright creatures can see farther, but will fall farther when taking a tumble. Horizontal ones may miss the view from above, but can easily put a nose to the ground to track a scent. And so on.

Any trait value only comes from important add-ons, such as restrictions on limb use. A four-legged creature without arms isn't suffering any disadvantage from horizontal posture; it's just walking on all its legs, which is what legs are for. But a humanoid walking on hands and feet does suffer the loss of arm use while walking. The condition is easily handled as a reduction on the cost of the arms.

Example: GURPS builds a lion with Extra Legs, No Fine Manipulators, and Horizontal; GULLIVER uses Extra Legs, No Arms, and the 0-point effect horizontal. GURPS builds a chimp with two legs, two arms, and Semi-Upright; GULLIVER uses two legs, two arms with a limitation on arm use, and the 0-point effect semi-upright.

Stance: Posture refers to how you position your body; how you position your legs is called Stance.

Legless creatures: For legless creatures, an upright posture means you keep one-third or less of your length on the ground. A semi-upright posture means about one-half of your body length on the ground. A horizontal posture means most of your body length on the ground. Consider a level of Improved Balance for semi-upright posture, and two or more levels for horizontal.

Body Plan options: symmetrical; asymmetrical; radial; Centauroid or other "hybrid form"; Amorphous Body; Limb Extrusion; Inconvenient Form; exotic (No Physical Body; other); posture (horizontal; semi-upright; upright; other).


What's your design made from? Boring organic flesh holds a monopoly in the real world, but don't let that stop you from using something weirder.


"High-density" flesh is a comic-book favorite. Choose your density (D), stated as kilograms per liter. That's 1 for water or most flesh.

Modified Density: Replace GURPS' Increased Density with a Modified Density package trait; cost is that of component traits only.

To build the creature, multiply mass by density. ST, HP, and DR or Toughness will likely be affected; consider multiplying these by (D + 1) /2, or by D for more extreme stats. (Assume base DR or Toughness of at least 1 for flesh denser than human.) Consider the Fragile disadvantage for D less than 0.75 or so. Pay for all of these normally.

Your encumbrance level will change, especially in water (see Book 2 for details). Purchase normally. If you have density less than 1, you'll also float easily on water. This is generally very useful benefit: pay 1 point per +1 bonus on rolls to float.

If you're so light you float in air, that's Slow Fall or even Static Lift.

That covers the cost of Modified Density. Treat effects on knockback and slams as generic effects of mass, not effects of density itself. Other miscellaneous effects of weight are special effects.

Material and density: Rounded densities for some common substances: air 0; aluminum 2.6; antler 1.9; asphalt 0.7; bone 1.8; brass 8.5; brick 1.9; bronze 8.2; carbon, solid 2.15; concrete 2.4; coal 1.5; copper 8.7; cork 0.25; earth, dry 1.25; earth, wet 1.6; earth, dense 2.0; fat (human) 0.94; glass 2.6; gold 19.3; granite 2.7; ice 0.9; iron 7.2; lead 11.4; marble 2.5; mercury 13.5; muscle 1.05; petroleum oil 0.9; platinum 21.5; porcelain 2.4; quartz 2.6; salt 1.4; sea water 1.025; shell (mollusk) 2.7; silver 10.5; snow, loose 0.15; snow, compact 0.5; steel 7.9; tin 7.4; wood 0.4 to 0.95 (depending on type). You'll find lots more at this off-site link.

Variable Mass: If you can vary your density by varying mass (without varying volume), you have an exotic ability:

Variable Mass (new)

2 points/level

You can adjust your mass, which in turn affects density and buoyancy. Each level of increase lets you increase starting mass using the progression x1.1, x1.15, x1.2, x1.3, x1.5, x1.7, x2, x3, x5, x7, x10, x15, x20, x30... Each level of decrease lets you decrease mass, using the same progression as a divisor.

Pay the above leveled cost, and pay for the best level of encumbrance you can achieve, and for any other beneficial effects of density you're capable of achieving (such as flotation bonuses), as above.

Variable Volume: The exotic ability to vary your density by varying volume (without varying mass):

Variable Volume (new)

1 point/level

You can adjust your volume, which in turn affects density and buoyancy. Each level of increase lets you increase starting volume using the progression x1.1, x1.15, x1.2, x1.3, x1.5, x1.7, x2, x3, x5, x7, x10, x15, x20, x30... Each level of decrease lets you decrease volume, using the same progression as a divisor.

Pay the above leveled cost, and pay for the best level of encumbrance you can achieve, and for any other beneficial effects of density you're capable of achieving (such as flotation bonuses).

Example: A fish (D = 1) has a gas-filled swim bladder that lets it multiply volume by one level [1] (D becomes 1/1.1), or lets it divide volume by one level [1] (D becomes 1.1). Either adjustment adds encumbrance in water (sorry, no points; the added encumbrance is voluntary), but increasing volume confers a +5 to float [5]. Total cost is 7 points.

That's about the limit of density change for a real creature. You can have greater Variable Volume that doesn't affect density, like a puffer fish that can balloon up by sucking in water. This fish would pay the same 1 point per level of increase, but there'd be no other effects to pay for.

Gas bag: A big gas bag may help you float, but can rupture. Cutting or impaling damage of HP or less hurts you normally without piercing the bag. (DR protects the bag normally.) Damage above that causes a leak, with flotation leaking out in an hour at HP/10 damage, a minute at HP damage, and instantly at HP x2 damage. Extrapolate other damage levels appropriately.

A gas bag is a base -20% limitation on anything that would be lost through rupture. Increase limitation value for the following:

Your gas bag is weak. Reduce HP for purposes of springing a leak by the following: x2/3 [-5%], x1/2 [-10%], x1/3 [-15%], x1/5 [-20%], x1/10 [-25%].

Your gas bag leaks fast. Use the same damage multipliers and limitation values as above, reducing HP for purposes of how fast you lose buoyancy.

Your gas bag makes you big, adding to your target size. The bag can be targeted separately; shots aimed at the whole target will have a chance of hitting the bag. Add the gas bag's volume to yours and figure your Size-based TH modifier from the Scale Table. Each +1 TH added is a -5% limitation.

Example: You gain the benefits of Slow Fall (no fall) [20], Static Lift [10], and +6 to float in water [6] from a fixed-size, fragile hydrogen bag. Tying these goods to a gas bag confers a Limitation value of -20% on their cost. You now add -15% for a fragile x1/3 HP for rupture resistance, -10% for x1/2 HP for rupture speed, and -15% for adding 3 to your Size as a target (volume x30). That's a net -60% limitation on the goodies [36, -60% = 15].

If it's a freely inflatable gas bag, also take Variable Volume (14 levels for x30 volume), for another [14, -60% = 6] points.

You need to heal damage to a ruptured bag to restore lost abilities. Try Regeneration (Gas Bag Damage Only: -80%) for a self-patching system.

Nature uses no gas bag designs, despite proven technology for extracting hydrogen from water (photosynthesis). In any case, a gas bag is unlikely in a small design. The small lift of a small bag will mandate light, thin walls, and that raises problems with structural integrity and gas penetration.

Inorganic life

Unusual Biochemistry, Restricted Diet, or Delicate Metabolism are likely in an inorganic composition, along with special life support requirements, Vulnerabilities and Weaknesses, and Modified Density. It's all speculation, so add whatever powers and weaknesses you like. The ever-popular "silicon-based life form", for example, might have as little difference from us as Delicate Metabolism and an extra 10% or so body weight – or tons of weight, massive ST, HP, and DR, and Body of Stone for that B-grade movie "rock creature" feel.

Composition options: organic; inorganic; density (Modified Density, Variable Weight, Variable Volume); exotic (Body of Ice; Body of Water; Body of Air; Body of Fire; Body of Earth; Body of Stone; Body of Metal; Insubstantiality; Astral Entity; Shadow Form).


How big is your creature? Use GURPS' Size and Speed/Range Table, or the Scale Table and copious suggestions from Book 1, to estimate your TH modifier from Size.

Size is power: it'll affect ST, HP, DR, and weight. You could set these values now, but it's easiest to build the creature as if it were normal-sized, and "scale" stats at the end.

Size trait

Size also affects Move, Reach, and sustenance requirements. You can adjust these with existing GURPS rules, using appropriate levels of Extra Reach (purchase separately for each appendage), Reduced or Enhanced Move (purchase separately for all modes of movement), and Decreased or Increased Life Support.

GULLIVER instead wraps up adjustments to Move, Reach, sustenance requirements, combat effects (including TH modifier), and other effects into a one-shot purchase of Size itself as a trait. (Inconvenient Size remains a separate disadvantage.)

Size (new)

10 points/level or 0

You're significantly bigger or smaller than the default size (usually human). Your level of Size is the same as your TH modifier for size: Size -1, Size +3, etc.

Find your Size on the Book 1 Scale Table. Multiply default air, water, and food requirements by Area Scale. Multiply Reach for all appendages by Linear Scale.

Multiply Move by Linear Scale. This adjusts Move for any physical mode: running, swimming, flying, climbing, etc. It's a large adjustment, but Book 2 natural encumbrance rules bring Move back toward the center. (If you don't use those rules, the adjustment is too extreme; see a simple fix in Book 1.)

Size-related adjustments to ST, HP, and DR are purchased normally, and are not included in Size.

Cost of Size is 10 points per level above 0, and 0 points for any level below 0.

The Size trait replaces GURPS' rules for characters with Growth or Shrinking made permanent. Costs may differ, as the approaches are very different. GURPS rolls size and stats into one point cost for permanent Shrinking, while it keeps size costs and stat costs separate for permanent Growth. But GULLIVER keeps Size costs and stat costs consistently separate in both cases.

For the ability to shrink or grow at will, see Variable Size.

Inconvenient Size

Inconvenient Size (new cost)


This is a variety of Inconvenient Form (above). Use a cost range of -5 to -15 points for either large or small creatures; see Book 1 for guidelines on setting cost. You can combine points for both odd size and odd shape, but total points for both should be limited to -15, or by the Overlapping Disadvantages rule, as the GM decides.

Advanced rule: odd shape and Modified TH

Book 5 contains an option for targets that are particularly wide or narrow, affecting attackers' TH. Use these costs for Modified TH: 10 points for -1 on foes' TH, 20 points for -2 TH, and 5 points per -1 TH thereafter; or -10 points for +1on foes' TH, -20 points for +2 TH, and -5 points per +1 TH thereafter.

Use these costs to buy additional Modified TH beyond what Size includes. Halve value of Modified TH that affects only thrust/missile attacks or only swung attacks.

Example: You're Size -3, but +1 TH for squarish build (net -2 TH). You lose that third point of Modified TH built into Size, and gain back 5 points.

Example: You're 13 feet long and buy Size +2 for 20 points. The purchase includes -20 points of Modified TH.

But you're 7 inches wide (Size -6). Your net TH is +1 for swings, -4 for thrust/missile attacks. Starting over from TH 0, your +1 TH is worth -10 points, halved to -5 for swings only. The -4 TH is worth 30 points, halved to 15 for thrust only.

Your Modified TH is a net 10 point advantage, not a -20 point disadvantage. Pay 30 points to make up the difference; the net cost of your Size is 50 points.

Size options: Increased Size or Decreased Size (or Increased/reduced Reach; Enhanced/Reduced Move; Increased/Decreased Life Support); ST; HP; DR; Inconvenient Size; Modified TH for shape; weight.

Supporting Structure

You can house a hidden endoskeleton, flaunt an obvious exoskeleton, or get by with neither. Exoskeletons will often offer DR, the equivalent of a carapace or armor plates (CI p. 57), but the body may be less flexible (see Flexibility). Either skeleton can suffer broken "bones".

No land creature with an exoskeleton is large, possibly because the impact of walking is harsh on a shell over time. Other than that, scientists debate the relative merits of exoskeletons and endoskeletons; the differences aren't important in the game.

A creature's supporting structure might affect the sturdiness of a body; use the modifications from "Structural Soundness", especially the Fragile disadvantage.


A creature that has no skeleton is an Invertebrate (for game purposes). It supports itself through hydrostatic or other means. GURPS has Invertebrate (CI p.102), but GULLIVER uses this package:

Invertebrate (revised)

varies (package)

You have no bones. Your appendages can be crippled normally, but you do not suffer broken bones. Take +2 on rolls to recover from crippling limb injuries (BS p. 129), +2 on Escape, and +2 on rolls to escape from or resist locks and holds.

On the down side, you have no free skull DR, have only x2/3 HP for determining the amount of damage needed to amputate an appendage (see Book 6), and take -2 on HT rolls to prevent such amputation! The GM can also limit body armor to scales, fur, or Toughness only, as additional DR would imply an exoskeleton.

These effects balance out to 0 points. Now purchase a lower Load ST. This can be one-fourth starting Load ST, as GURPS suggests, or any other level.

Finally, add Double-Jointed, Flexibility, Extra Flexibility, Squishy, or even Stretching.

Cartilaginous (new)

varies (package)

You have a cartilage-like supporting structure, with effects somewhere between Invertebrate and a skeleton. You can suffer broken "bones", though the injury heals twice as fast as skeletal breaks. Take +1 on rolls to recover from crippling limb injuries (BS p. 129), +1 on Escape, and +1 on rolls to escape from or resist locks and holds.

On the down side, you have half normal free skull DR, have only x4/5 HP for determining the amount of damage needed to amputate an appendage (see Book 6), and take -1 on HT rolls to prevent such amputation.

These effects balance out to 0 points. Now set and purchase a lower Load ST, though not as low as you would for Invertebrate. Consider adding Double-Jointed, Flexibility, Extra Flexibility, or Squishy.

Extra Encumbrance

Thick blocky bones, multiple legs, or a loosely-defined superior load-bearing design, as in FF's Dwarves, will support more weight. Build this with Extra Encumbrance (CI p.54). The "None" to "Super-Heavy" levels of WSR become 17, 20, 25, 35, 45, and (presumably) 60.

GULLIVER reworks this into a leveled trait, each costing 5 points. For "None" or greater levels of encumbrance, one level takes the amount of WSR cutoff over 15 and mutiplies it by x1.5. Two levels multiplies it by x2, three levels by x3, five levels by x5, and so on.

Suggestions for buying levels:

See Book 2 for details.

Supporting Structure options: endoskeleton; exoskeleton; Invertebrate; Extra Encumbrance; Load ST; other options in Structural Soundness and Flexibility below.


Here's where you set your ST. It's easiest to first imagine a "base ST", or what ST would be if your design were human-sized. Use human guidelines: ST 7 for a scrawny build, ST 12 for a stout one, ST 14 and up for heavy muscles.

That takes care of base muscle quantity, but how about quality? Muscle strength is surprisingly uniform for most earth creatures, even insects, so you don't need to make any change here for animals. But modify base ST as you wish for unusual muscle composition – say, x1.5 for stereotypical "dense" alien tissue or x3 for "magically" strong flesh (wee folk races in games usually possess several times their apparent ST).

Set aside this base ST, and scale it for size later.

Type of muscle: Instead of normal high-output muscle ("light meat" in animals), you can specialize in sustained-output muscle ("dark meat"). Use a lower base ST, and add Extra Fatigue.

Natural ST

GULLIVER offers fixes for the problems addressed by the Natural ST limitation, making it unnecessary. Drop Natural ST from the game, and see Book 1 for much more on strength.

ST part by part

A single ST stat covers all of a creature's muscle groups, for simplificity. For detail, see later notes on arm, manipulator, striker, wing, leg, jaw, and other ST modifications to adjust power in specific parts.

Locking Muscles

Here's a real-world variant of muscle:

Locking Muscles (new)

5 points

Like a shellfish's adductor muscle, your muscles have an efficient mechanism for "locking" into a contracted position. You can maintain a chin-up or support a weight at arm's length with no fatigue for short periods of time (use 1/10 normal fatigue if the time stretches into minutes or longer). Your muscles relax normally if you lose consciousness.

Locking does not make you stronger; your locked grapple or bite can be overcome normally. (Increase ST if you want an "iron grip" or "jaws of death".) But a foe who fails to pry a diamond from your grip will suffer fatigue over repeated attempts; you won't. If you can resist those early attempts, you'll have the contest in the bag as he tires.

Locking does not lower fatigue from intitial muscle contraction, movement, or ongoing effort; there's no benefit for regular actions like running, lifting, crushing a beer can, or any application of Extra Effort. Apply half fatigue for borderline cases like climbing (the pulling and pushing is fatiguing to you, but maintaining grips and holds isn't).

On Earth, only certain mollusks have Locking Muscles; these also contract quite slowly, so add low DX or low Speed if you like. A bulldog's "locking" jaws rely on simple strength and stubbornness, not Locking Muscles, but apply the trait if it sounds fun. Also see Deathlock below.

Limitation: You can lock one set of muscles (such as jaws or one hand; -60%), two sets (such as two hands; -40%) or a larger subset of the body (such as all arms or all legs; -20%).

Deathlock: This is similar to but separate from Locking Muscles. Any strongly contracted muscle stays contracted even after unconsciousness or death! Fatigue will eventually loosen the "deathlock" normally for most creatures, although Locking Muscles might stay contracted for days. Deathlock is worth 1 point for any creature.

Musculature options: ST; fatigue options (Reduced/Extra Fatigue); unusual muscles (Locking Muscles; Deathlock). Further adjustments are available for individual body parts.

Body Fat

Use the Skinny disadvantage for little fat tissue, and Overweight, Fat, or Obese for a lot. (A character with high weight from big bones or natural armor may have encumbrance as a disadvantage, but that's not Fat.)

Encumbrance will vary greatly by individual, depending on the character's ST and final weight; in a very light character, Fat might only reduce the level of negative encumbrance, without adding any positive encumbrance. For that reason, GULLIVER bases the cost of Fat on final effects, including Book 2's costs for natural encumbrance:

Fat (new cost)


Choose a level of Fat below. Weight additions are only guidelines; adjust as you like. See BS pp. 28-29 for details of the reaction penalty and other miscellaneous effects.

For simplicity, treat other characteristics of Fat as special effects. These include miscellaneous nuisances, different encumbrance levels in your non-primary Environment, bonuses to float in water, and benefits in close combat. (See Book 2 to compute encumbrance and floating bonuses in water.)

Example: A human who gains Heavy encumbrance on land from Obese has -40 points for encumbrance, and -10 for reaction penalties. Changed encumbrance level and floating ability in water, as well as problems with clothing, etc., are all no-cost effects.

Health effects: To represent strain on the heart and other organs, consider reducing HT by 1 for a character with Medium encumbrance from Fat, or 2 for Heavy or greater. Purchase normally.

Energy store

Fat is stored energy. Consider a level of Reduced Fatigue for a Skinny character, and up to a level of Extra Fatigue for each level of Fat. Of course, fatigue penalties from the encumbrance (see Book 6) may use up that Extra Fatigue quickly!

Fat's even more important in surviving long-term food deprivation, including hibernation (see Book 6); call it a free special effect of your adipose.


Thick blubber is an effective insulator in cold weather (but possibly harmful in hot climes). Move your temperature "comfort zone" down a few degrees, and add additional Temperature Tolerance versus cold.

Body Fat options: Skinny; normal; Fat (Overweight; Fat; Obese); Reduced/Extra Fatigue; Temperature Tolerance (versus cold).

Structural Abnormalities

What humans call abnormalities or defects may be normal traits in other species. Game effect is what counts: your weak-spined alien PC gets full points for Bad Back, even if he's a flawless specimen of his own species.


The Dwarfism disadvantage deserves a closer look:

Dwarfism (revised)

varies (package)

Build dwarves using overall small size, or unusually short limbs, or both. Cost is only that of included traits:

Add appropriate traits for the character's status or reaction adjustments in the campaign.


Gigantism doesn't quite bring a character up to the next Size. The disadvantage cost comes mostly from reaction penalties, with a few extra points for minor Inconvenient Size effects. Weight should be high, so a giant might gain additional points from encumbrance.

Gigantism is often an unhealthy condition. Consider Reduced Move, low DX, or low HT, bought separately.

Back troubles

A suggested modifier to Bad Back's HT roll to avoid back trouble: add your Half modifier for encumbrance. Lots of weight isn't going to help those poor vertebrae!

Structural Abnormality options: none; Dwarfism; Gigantism; Bad Back; Hunchback. Related options are in Structural Soundness below.

Energy and Chemistry


Respiratory medium

You can breathe air or breathe water (i.e., extract oxygen from these); choose one by default, or both using Gills. (A water-breather uses oxygen-extracting membranes called gills, but for game purposes Gills is the name of an advantage allowing both air- and water-breathing.)

Environment and respiration

Respiratory medium is a 0-point default – with an exception. If you're strictly aquatic and breathe only air (no Amphibious or Gills), take Environmental Intolerance (need air) [-20]. This is a special Environmental Intolerance with its own effects. You need to hit the surface to breathe; getting trapped underwater will be fatal! Consider Oxygen Storage and Breath Holding to boost your default breath-holding ability (BS p. 122); also see Catsleep for the ability to surface on autopilot.

Dolphins and whales all have this disadvantage. (A hypothetical terrestrial-only creature that respires only in water would be in the same fix, needing to dunk its head periodically to breathe.)


Also consider Doesn't Breathe – which, by the GURPS description, is compatible with any form of breathing! The name is misleading: you do need to breathe, but do so through your skin, not with lungs.

Below is a reworked, renamed version, with cheap, skin-based breathing later:

Reduced Air Requirements (new)

5 points/level (max 5)

This is a form of Decreased Life Support for air. Each level reduces your oxygen needs, using the progression x1/2, x1/5, x1/10, x1/20, x0.

Two levels let you breathe in thin atmospheres, and four levels in trace. The fifth level is true Doesn't Breathe and removes all need for oxygen; you can be strangled but not suffocated.

Add +2 per level to rolls to resist respiratory poisons, with immunity at five levels. 


Old and new options:

Filter Lungs: This helps you breathe in the good without the bad, and is useful for people or fish.

Passive Respiration: You don't have to have lungs. Passive Respiration [0] means you talk via some means other than by shaping forced air, and can't blow out birthday candles. On the good side, you probably won't have your "wind knocked out" by a gut punch, or suffer collapsed lungs from injury.

This trait is appropriate for insects that get along with a passive or convection-based network of tubes, which may or may not limit Size to about -6. On the other hand, recent research suggests active respiration via tiny balloon-like structures in some insects; if that's the excuse you needed for bus-sized bugs in your game, go for it.

Separate/Inaccessible Respiratory Intakes: Whatever the mechanism, consider the system's openings. A human has only one (actually two, nose and mouth, but they cross in the throat, and are close enough together to both be covered at the same time by an attacker). Same with a typical fish: squeezing the gills shut is like putting a hand over a human's nose and mouth. This is the 0-point default.

Separate Respiratory Intake [1] neatly separates breathing and eating intakes – no choking on food or on gags. This works for fish, alligators, etc.

Inaccessible Respiratory Intakes [2] means several separate intakes, or completely inaccessible ones. No one's going to kill you with duct tape or a pillow (well, maybe lots of tape, or a big pillow). If you have Gills, buy this separately for air and water.

Your internal intake tubes in your neck(s) are still vulnerable to crushing and so on, but see No Vulnerability: Neck.

Holding breath

No Respiratory Shutoff: You can't close off your intakes. No Respiratory Shutoff [-2] doesn't mean you automatically suck in water when swimming, but you can't hold breath. What's in your system is used up in one-fourth the time of held breath, after which you start suffocating. Rolls to avoid drowning might be at -2, and rolled every minute instead of 5 minutes. The GM can apply similar penalties around poison gases.

No Respiratory Shutoff goes well with Passive Respiration. A terrestrial insect combines these with Inaccessible Respiratory Intakes, for a net 0 cost.

No Breathing Shutoff: A stronger version of the above, No Breathing Shutoff [-5] means you have lungs and can't stop active breathing. You suck up poison gas with fervor and go back for more. Underwater you take in water immediately. This is obviously a lousy choice for aquatic air-breathers.

Storage traits: Incompatible with the above two disadvantages, Oxygen Storage (gives one-hour breath-holding time) and Breath Holding (each level doubles breath-holding time) let you go long without breathing. Let their effects be cumulative. Both are good choices for aquatic air-breathers.

Osmotic breathing

Being able to breathe through your skin instead of the usual means is a 0-point effect: think of it as Inaccessible Respiratory Intakes [2] plus the problem that heavy clothing will hamper breathing [-2, details up to GM]. A fixed combination, such as always taking in half your air through lungs and half through skin, is also possible for no cost. Breathing through skin works in only air or water, not both, by default.

Being able to choose how you breathe is an advantage: a poison affecting one intake might not affect the other. For any one medium (air or water), call lungs or skin your norm, and add the ability to switch fully or partially to the other through Reduced Air Requirements at -80% cost.

Example: You breathe air normally through lungs [0], but can also do so through your skin. When you choose to breathe air through your skin, your lungs need only 1/5 the air [Reduced Air Requirements x2, -80% = 2]; your skin provides 4/5 requirements. (Total requirements are unchanged.)

If you add another medium to the mix, do the same but use a -60% limitation. The purchase is essentially cheap Gills:

Example: A frog breathes air through lungs [0]. Its skin doesn't help in air [0], but underwater the lungs need only provide 1/10 normal air (i.e., can hold breath 10 times as long) with the skin providing 9/10. Buy that with 3 levels of Reduced Air Requirements [15, -60% = 6].

Point accountants will note that normal lung breathing ability [0] plus full skin breathing ability in air [Reduced Air Requirements x5, -80% = 5] plus complete skin breathing in water [Reduced Air Requirements x5, -60% =10, essentially Gills] plus added lung breathing in water [Reduced Air Requirements x5, -80% = 5] gives you the same cost and effect as GURPS' Doesn't Breathe.

Exotic gases

Default: Replace oxygen with another default requirement, as you like. This may count as a Dependency if you're off-world.

Additional Atmosphere: The ability to breathe more than one gas or atmosphere type is an advantage: Additional Atmosphere [10 per additional atmosphere type or a pure common gas (i.e., nitrogen)]. Halve cost for rare atmospheres or gases; see CII p. 136 for a bestiary of atmospheres.

Add Nuisance Effects if use of the secondary gas saddles you with problems. ("Let me clean you up, Captain; I should have told you pure carbon dioxide makes the troops hallucinatory and... uh, randy...")

Others: Anaerobic is simply a switch from oxygen to something else, with a Vulnerability to oxygen. That's a big disadvantage in human-occupied areas, but would be worth nothing in your native habitat.


A common Dependency is some substance that aids respiration. Many creatures require moist skins to efficiently absorb oxygen; a Dependency on moisture, osmotic breathing, and Slime go well together.

The effect of such a Dependency will be suffocation (first fatigue damage, then regular damage). Halve Dependency value.

Fatigue-related traits can model respiratory efficiency. (Be sure to price incremental Fatigue lower than incremental ST: cut cost to half that of incremental ST when the latter is worth 5 points or less.)

Respiration options: medium (air-breather; water-breather; Gills; Breathing Dependency (air); Breathing Dependency (water)); gas (oxygen; non-oxygen gas; Anaerobic; Additional Atmosphere); Reduced Air Requirements; intake (normal; Passive Respiration; Separate Respiratory Intake; Inaccessible Respiratory Intake; No Respiratory Shutoff; No Breathing Shutoff; osmotic breathing); breath holding (Oxygen Storage; Breath Holding); Filter Lungs; fitness options (Reduced Fatigue; Extra Fatigue; Fit; Very Fit; Unfit; Very Unfit); Dependency.

Diet and Digestion

Herbivores eat plants, carnivores eat meat, omnivores eat both, and ergivores draw nutrients from the environment. Within those categories are terms to describe how you get that food, which in turn suggest appropriate behavior and traits:

Other words cover specializations: an insectivore is a bug-eating carnivore, but can be a chaser, pouncer, etc.


There's no free breakfast, lunch, or dinner in nature. Carnivores need to hunt things down. Herbivore fare is usually more plentiful and certainly more compliant, but the lower energy value means it takes a lot to make a meal. Omnivores have the luxury of choice, but usually need a balanced diet, not purely meat or greens. (A person eating only meat or only low-protein greens will have problems; get creative with nutritional disorders, or treat as very slow starvation.)

See Book 6 for basic food needs. Your base requirements are a 0-point effect.

Increased Life Support: Your food is hard to come by, or you need great quantities. Use one level of Increased Life Support per doubling of base food needs, at -10 points per level. But if you're smaller than the campaign norm, allow only -2 points per level of Increased Life Support, until food requirements reach normal levels. Even if your 1" PC eats four times what his size suggests, that's still a tiny smidgen; his big pals can stuff him to the gills with nothing more than crumbs!

Decreased Life Support: Your food is particularly plentiful, or you need very little. (Universal Digestion and Cast Iron Stomach also boost your food supply.) GURPS' 10-point cost is too expensive, the same as Doesn't Eat or Drink! Instead, let each level cost 2 points and reduce requirements using the progression x1/2, x1/5, x1/10, x1/20, x0. Five levels [10] becomes Doesn't Eat.

Special needs

Restricted Diet: Here's a more tailored trait to cover unusual requirements:

Restricted Diet (new)


This is a version of the Dependency or Increased Life Support disadvantages. You survive only on certain foods. Use the Dependency base costs (-5 points for Common foods, -10 for Occasional, etc.) but with no frequency modifier. Rather than damage as described for Dependencies, starvation rules apply when you miss meals.

Pandas and koalas are finicky examples that vex zookeepers. Restricted Diet is very likely in beings from another world (as is Unusual Biochemistry, but that gives you problem with local drugs, not food). Other food sources might serve in a pinch, but may be hard to obtain, hard to stomach, or low in nutritional value for you, with each "meal" counting as only a fraction of a real meal. (You can test borderline foods with the Unusual Biochemistry rules' die roll.)

For a more serious version of the disadvantage, use Delicate Metabolism.

Actual Dependencies – calcium, gold ore, fresh brains, Trix – add zest to a diet but are best suited to exotic designs.

Vampiric Dependency is a non-paranormal disorder that requires consumption of human blood (or the blood of the campaign default species); its high -50-point value stems from its Restricted Diet component, the need to murder, and the danger from torch-wielding peasants.

Diet and Digestion options: herbivore; carnivore; omnivore; ergivore; exotic (eats rocks, steel etc.); Parasite; required level of sustenance (Doesn't Eat or Drink; Decreased Life Support; Increased Life Support); diet requirements (Dependency; Delicate Metabolism; Restricted Diet; Vampiric Dependency; Universal Digestion; Cast Iron Stomach); Slow Eater; other mouth options.

Other Metabolism options

Also related to your efficiency in metabolizing inputs are traits that range from the mundane (Alcohol Tolerance) to the fantastic (Altered Time Rate). Fitness modifications can stem from metabolism too (see earlier notes on high ST and the cost of Extra/Reduced Fatigue).

Other Metabolism options: normal; Slow Metabolism; Altered Time Rate; Hyper-Strength; Hyperactive; Metabolism Control; Sanitized Metabolism; Unusual Biochemistry; alcohol metabolism options (Alcohol Tolerance; Light Hangover; No Hangover; Alcohol-Related Quirks); poison metabolism options (Resistant to Poison; Immunity to Poison); fitness options (Reduced Fatigue; Extra Fatigue; Fit; Very Fit; Unfit; Very Unfit).

Chemical Production

Our bodies are walking drug factories, churning out the chemicals that account for digestion- and metabolism-related traits. So if you've brewed up some particularly funky pharmaceuticals, why not get fangs and share with your neighbors?

Venom offers a variety of types and delivery methods (CI p. 71). A sprayed irritant venom is perfect for bombardier beetles.

If your venom doesn't affect yourself, let that be a +10% enhancement, or +20% if you also have the cloud of mist enhancement. If your venom is a racial trait and doesn't affect your own kind, that's a 0-point effect: you won't hurt yourself, but can't hurt foes within your race either.

Many poisonous creatures loudly advertise with "stay away from me" color.

Pheromones are friendlier than pesticides. Bio-Tech offers Charisma based on scent for a -20% limitation.

Passive venoms

Many animals' flesh is poisonous. This is more payback than defense! Start with the -70% Sweated Venom limitation from CI p. 71, but rename it Passive Venom. You only deliver venom when handled excessively or bitten for damage. Add other enhancements as you like, for squirts or sprays to surprise manhandlers.

You can even build a passive contact agent: it only works when you're touched or grappled, not when you touch or grapple someone. Good luck explaining why.

Let a Passive Venom squirt attack have a range of twice your Linear Scale; the liquid hits on a 12 or less, and is Dodged at -2. Adjust as appropriate: a hand sticking a knife in you, or a biting mouth, is likely to get splashed automatically!

Variable Dose Passive Venom: Give as good as you get! With this variant of the Passive Venom limitation, the dose you deliver depends on how badly you get hurt.

You deliver a full dose of ingested venom when bit for half your HP in damage. One-quarter HP damage delivers half a dose, and less damage means no delivery. Full HP damage delivers two doses, and twice HP damage delivers four doses. A foe who actually eats you takes a quintuple dose of poison (also the max he can take from any amount of biting or contact).

Squirts and sprays work the same: the amount released is determined by the amount you're hurt. Let that be a variable dose, as above, or a fixed, full dose with a variable range/radius. Choose one at the time of design.

A contact agent delivers a full dose of venom when you're hit with a grapple; lesser touching delivers less damage, while a full-body naked grapple would deliver multiple doses.

This variant uses Passive Venom's -70% limitation value. But halve the value of additional venom enhancements. Contact venom becomes a +35% enhancement, squirted venom a +20% (rounded up), and sprayed venom a +50%. You'll get fun out of these enhancements only when you're getting killed, so a lower cost is fair. Revenge is cheap!

Example: Hard-shelled, carnivorous aliens have acid blood that splashes dangerously when they're injured (3 levels of corrosive venom). Take the -70% Variable Dose Passive Venom limitation and tack on a half-cost Squirt enhancement for +20%, leaving a net -50%. The harder you blast 'em, the worse they spew!

Chemical light

Here's a new advantage stemming from an internal chemical reaction:

Bioluminescence (new)


You can emit flashes of light, useful for signaling or illumination. Decide which body part(s) shine, or whether your whole body does. For 5 points you have a "Size -10" glow, where Linear Scale for that Size is the distance at which the light allows reading. Each additional point adds 3 to this "Size", up to 10 points (Size +5).

Beyond 10 points, you're putting out blinding light. Each extra point in Bioluminescence increases the light's "Size" by only 1, not 3. Take your "reading light distance"; anyone within x1/50 that range will be hit by a blinding flash of light, those within x1/10 that range may be affected (GM call), and those within x1/5 that range are only affected slightly, and then only on a failed HT roll. See Flash attack (CI p.72) for effects. (Yes, 15 points of Bioluminescence is this Flash attack.)

To spot bioluminescent light at night, make a Vision roll, with modifiers for Range and the light's "Size". Reverse penalties for darkness, so that total darkness gives a +10! Add +6 for a flash, as the eye catches movement easily.

Round things out with limitations: a firefly has 5 or so points of Bioluminescence with Takes Recharge [-10%]. Take a -20% for Always On if you can't turn off your light; you're continually flashing or shining!

Enhancement: Your can choose to shine steadily. This is much more useful than a quick flash for reading or exploring! +20%.

Enhancement: You can reduce the power of your light output. This is useful for signaling a nearby friend without alerting faraway enemies, or lighting up a room without blinding everyone! +20%.

Enhancement: You can shine from any or all body parts, as you choose. +10%. This goes well with the above variable-output enhancement.

Enhancement: You can flash quickly enough to send Morse code, if you have the skill. As blinding flash attacks, these pulses still count as one attack per turn. +10%.

Enhancement: You can shape your light into a beam. This makes the light a DX-based attack to "hit" a target, but increases its "Size" by 3 in that direction only. +20%, or no enhancement if you can only make a beam.

Enhancement: You shine in some spectrum other than visible light, such as Infrared or ultraviolet. This is a 0-point effect. If you can shine in visible light and other spectrums, that's a +20% enhancement per additional spectrum. (If your spectrum adds powerful capabilities – like cooking foes with microwaves – that'll cost a lot more, as the GM decides.)

Enhancement: You can control your frequency within your spectrum(s). Within the visible light spectrum, you can shine with any color of the rainbow. +20%, or +30% for the ability to emit multiple frequencies at once (to make a shower of rainbow-colored light, for example).

Replace the Illuminate superpower with Bioluminescence if you like, and rename the whole thing Light for a simpler name.

Chemical Production options: normal; Drug Factory; Pheromone Control; Venom; Bad Smell; Bioluminescence; Charisma (scent-based: -20%).

Thermal Regulation

Comfort zone and tolerance

You have a default "comfort zone" of about 55° and worth no points, even if you center the range on a bizarre temperature. Temperature Tolerance extends that zone in one direction by HT degrees per level.

Sea creatures may need to set their comfort zone low for cold waters, but have little need for Temperature Tolerance. Nowhere in the open ocean does water temperature vary by more than 15° throughout the year.

Intolerance: Temperature Intolerance is quite possible, due to low body fat on the cold end, and lack of a sweating or panting mechanism on the warm end. Shrink your comfort zone by 5° for every -2 points. For -20 points, you have an extremely narrow comfort zone of only 5°!

Temperature Intolerance is appropriate for many fish, who are easily harmed by temperature fluctuations. Migratory fish should maintain a fairly wide comfort zone, though.

Advanced rule: Book 6 offers a rule that treats heat loss in water more realistically. It triples any temperature difference between water temperature and a creature's optimal environmental temperature, for purposes of comparison with "comfort zone".

The rule gives swimmers a narrow effective comfort zone even without using Temperature Intolerance; Temperature Tolerance will be important for far-ranging fish! (Note: this rule makes no change in the "stiffen-up" temperature of Cold-Blooded creatures; that's based on absolute temperature.)

Warm and cold blood

A creature either regulates its temperature internally (warm-blooded) or does not (Cold-Blooded). Mammals and birds are warm-blooded endotherms, while lower creatures are cold-blooded ectotherms – but don't feel too bound by that. A popular theory holds that dinosaurs were warm-blooded, and zoologists note that some large fish have heat exchange mechanisms so efficient they're effectively warm-blooded.

Cold-Blooded life: If cold-blooded, you eat less (x1/3 default levels for game purposes) and may be able to drop into "suspended animation" torpor to survive cold. As long as you don't freeze solid, the GM should let you ride out long freezes with little damage and even lower food, air, and water needs than usual. (Cold-based attacks affect you normally!)

Cold-blooded creatures can maintain a remarkably even body temperature by varying their behavior and using sun and shade. You can raise your internal temperature by sunning yourself or lazing on a hot rock – say, a 5° rise after (your MAR x 30) minutes of warming. Large wings, a sail, etc. will help you to catch the rays, lowering MAR.

Once you're warmed up, you may need to find shade to recover Fatigue after prolonged activity. Too much solar heating will harm you more than it will an endotherm, as you can't sweat it off (consider Temperature Intolerance on the warm end).

Technical notes: Temperature Tolerance to cold expands the bottom end of a Cold-Blooded design's comfort zone, but doesn't affect the "stiffen up" temperature below which it slows down.

Note that many fish make their homes in waters colder than this "stiffen-up" temperatures! Solve this oddity with a free tradeoff: trade up to 15° of high-end Temperature Intolerance for an equal reduction in Cold-Blooded's stiffen-up temperature. This lets the fish live normally in their natural cold environments.

Temperature Tolerance paired with Cold-Blooded is likely due to an internal effect, rather than the aid of fur, feathers, or blubber – these forms of insulation would hamper vital use of the environment to control body temperature.

Size and regulation

Small creatures lose heat much more quickly than large ones do. They make up for this by burning proportionately more fuel, i.e., eating a lot. This is built into the Size trait; see other notes in Book 6.

Other heat- and energy-saving tricks used by small creatures include careful use of the environment (above), long periods of sleep or inactivity, fat stored on the surface (beef is marbled; chicken meat is lean with fatty skin), and feathers or thick fur.

These modifications don't necessarily add Temperature Tolerance; rather, they prevent Temperature Intolerance, Reduced Fatigue, etc.! Use them if you want to give a small design a realistic feel. But below the several-gram weight of a shrew or hummingbird, even these tricks aren't enough to maintain proper heat; there's no choice but to go cold-blooded.

Thermal Regulation options: warm-blooded; Cold-Blooded; comfort zone (location of zone; Temperature Tolerance; Temperature Intolerance).

Health and Resilience

Structural Soundness

Health, Hit Points, and Damage Resistance

Set HT as you like. Wild animals likely have HT above 10 in order to survive, but anything over 15 should be extremely unusual. Don't confuse HT with HP; you want HP to vary with size, but not necessarily HT.

Extra/Reduced Hit Points and DR (or Toughness) also represent structural soundness. DR is usually described as natural armor. Toughness is more of an "internal" damage resistance, and a better choice than DR for dense or "rubbery" flesh.

For now, just set the "base HP" and "base DR" your creature would have if it were human-sized (see Book 1 for details). Scale HP and DR for size later. (Let Toughness scale too: a Giant should be allowed an appropriately scaled level of Toughness.)

Cost: Book 1 suggested optional pricing for DR, Toughness, and Extra Hit Points to address players' complaints with the relative costs of these advantages. A recap:

Extra Hit Points cost 5 points for one level, 10 points for two levels, and 2 points per additional level.

Toughness and DR share an identical cost: 10 points for one level, 25 points for two levels, and 3 points per additional level.

See Book 1 for further notes, including costs under GURPS' "ST=HP" option. Also see more on DR below.

Injury Tolerance

Injury tolerance traits like No Neck or No Brain are renamed in GULLIVER to "No Vulnerability: type". This is clarify their effect: the parts may or may not exist, but it's the indicated vulnerability that the trait removes.

For extra, non-human vulnerabilities, use Reduced Hit Points, Fragile, Vulnerability, Weakness, etc.

Here are yet more ways to hurt yourself:

Injury Intolerance (new)


Your internal vital organs are exceptionally delicate, or extend unusually far throughout your body.

Halve the value of Injury Intolerance in appendages if only one set is affected (legs but not arms, for example).

Apply appropriate effects: a non-brain target treated as a brain hit uses brain-like damage multipliers and stun effects (although it gains no free skull DR).

The worst combination you can come up with is treating any hit as a brain hit: head [-10], body [-30], and appendages [-20]. That nets you a big -60 points, but your first pillow fight may be your last.

Vital organ notes

No Vulnerability: Vitals removes your vulnerability to groin, kidney, and "generic" vitals targets. That includes the heart, which is treated on CII p. 53. (Book 5 suggests minor changes in heart size stats.)

Weak heart: Here's a common human ailment:

Weak Heart (new)

-10/15 points

You may not have HT over 13. You suffer -1 on all HT rolls for aging and to resist physical stress, including the effects of high gravity or acceleration, or unconsciousness or death from wounds. A critical failure on any such roll will trigger a heart attack in you, in addition to normal effects. Rolls to recover from serious internal injury (including heart attacks!) are also at -1.

Also roll vs HT to avoid heart attack in any situation of extreme mental stress (GM call). Fright Checks would be the main culprit. Make a HT roll at +5 , subtracting one-half the amount by which the Fright Check was missed. Also check vs HT +5 when Fatigue is reduced to one-half or less from physical (or spellcasting!) strain; check HT again at +3 if reduced to one-third, and check straight HT if Fatigue is reduced to zero.

Finally, treat any damage to the heart as double for purposes of HT rolls to avoid heart attacks (see Book 6 and CI p. 53).

Weak Heart is worth -10 points. A -15-point Very Weak Heart works the same, but the above -1 on certain HT rolls becomes a -2, and the above HT rolls to avoid heart attacks take a -4.

Organ size: As special effect, any specific vital organ can be made smaller to decrease target size, while increasing vulnerability if it is hit. Larger size has opposite effects. See "Brain Size" below for notes.

Modified Blowthrough

Another bit of weirdness:

Reduced Blowthrough (new)

5 points/level

Impaling or bullet damage "blows through" your form easily, most likely because you're flat and thin. Each level cuts "blowthrough" HP for all locations, reducing the damage that affects you.
















To vary blowthrough by location, cut the level cost to 3 points for the body (but not head!), and 2 points for all appendages. See "Appendage HP" to modify individual appendages.

Modifiers for body location, big bullets, etc. still apply before blowing through, and you take normal damage from cutting and crushing blows, flame, etc. (The No Impaling Bonus advantage doesn't negate Modified Blowthrough; arrows fly through you with lessened flesh damage, and that wound hurts you only like crushing damage.)

Limitation: Attacks from certain angles or to certain locations ignore your Reduced Blowthrough. Details are up to you, but generally foes can make those blows by taking a TH penalty. Limitation value is -80% for foes' -1 TH, -60% for a -2, -40% for -3, -20% for -4, and no limitation for -5 or worse.

Increased Blowthrough: For -1 point per level, your blowthrough damage level increases using the progression x1.5, x2, x3, x5. At -5 points, you have No Blowthrough: damage never blows through.

Structural Soundness options: HT; general bulk and soundness (Extra Hit Points; Reduced Hit Points); damage resistance (DR; Toughness); Extra Stun; Hard to Kill; Injury Tolerance (No Vulnerability: Blood; No Vulnerability: Brain; No Cutting/Impaling Bonus; No Vulnerability: Neck; No Vulnerability: Vitals); Modified Blowthrough (Reduced Blowthrough; Increased Blowthrough); weaknesses (Weak Heart; Injury Intolerance; Fragile; Vulnerability; Weakness).

Pain Tolerance

High Pain Threshold is a popular GURPS advantage, very powerful for its cost. Below is a stricter reworking in which increased tolerance brings its own troubles. Nature gave us a sense of pain for a reason...

High Pain Threshold (revised)

10 points

High Pain Threshold comes in three levels, all with the same point cost:

High Pain Threshold: Halve the pain and shock from any injury (or alternately, subtract 3 points; pick one method and stick with it). Take a +3 on rolls to resist torture, stunning, or other pain effects. This is an appropriate advantage for tough people and tough animals like wild boars.

Very High Pain Threshold: You feel almost no pain! As above, but quarter pain and shock (or alternately, subtract 6), and take +6 on appropriate rolls. Wounds do not reduce Move and Dodge until HP are below zero, and rolls to avoid unconsciousness from injuries are at +2. Very High Pain Threshold sounds right for sharks and lower life forms.

The downside: the GM secretly tracks damage. Wounds may not even be noticed during battle, and diseases may go unnoticed until symptoms other than pain appear.

A check over and Diagnosis roll can determine current HP. You will not instinctively favor injured areas; take a -2 penalty to healing rolls and rolls to resist long-term crippling. Also take a -2 penalty to rolls to reflexively avoid pain (such as a DX roll to remove your hand from a hot stove before taking damage).

No Pain: You feel no pain and suffer no shock penalties or Move or DX loss from wounds. Take +4 on rolls to avoid unconsciousness from wounds (or do so automatically, at the GM's option). But you won't notice wounds other than by sight or from the feel of impact; even a Diagnosis roll will only give you a rough idea of your state. Disease may go unnoticed dangerously long. Healing and crippling rolls as described above are at -4. Rolls to reflexively avoid painful stiimuli are also at -4, or fail automatically.

No Pain is best suited to undead creatures. With the exception of temporary berserk states, this rare condition is deadly when it appears as a human defect!

The "macho chip" from Cyberpunk and Ultra-Tech confers No Pain, but could be built to offer a lesser version.

Pain Tolerance options: normal; high pain tolerance (High Pain Threshold; Very High Pain Threshold; No Pain); Low Pain Threshold.

Immune System

Use the following to represent high or low immunity:

Immune System options: HT; Disease-Resistant; Immunity to Disease; Panimmunity; Weak Immune System; Cyber-Rejection; Vulnerability; Weakness; Dependency.

Radiation Tolerance

Many non-humans enjoy resistance to radiation (CII p. 148). PCs can purchase those benefits as follows:

Radiation Tolerance (new)

1 point/level

You're hardened to the effects of radiation. Each level gives you a Protection Factor (PF), using the progression PF x2, x3, x5, x7, x10, x20, x30, x50, etc. Five levels give you PF 10, etc.

Divide rads of exposure by PF, per CII p. 145; you can also divide time exposed to sunlight by PF for purposes of sunburn. (Or for minor hazards like sunburn, let the first 5 levels each add +1 to HT rolls to resist effects; 6 or more levels make you immune to such trivia.)

Radiation Intolerance: Multiply the effective rads of an exposure using the progression above, for -0.5 points per level (maximum 10 levels). The maximum -5 points multiplies exposures by 100.

Radiation Intolerance would also boost the effects of the low-level radiation we all receive every day. But rather than calculate daily rads, simulate these long-term effects with a lower HT. Save the actual rules for space trips and core meltdowns.

Radiation Tolerance options: none; Radiation Tolerance; Radiation Intolerance.

Motion and Gravity Tolerance

They say getting there is half the fun – but not when you're heaving over the side of the deck. Movement and gravity can really play with that inner ear.


GURPS' many intolerances to motion and travel can all be subsumed into a Weakness disadvantage. Cost ranges from -2 to -20 points, depending on severity; see Timesickness for a guide. Severe stunning, or an HT roll to avoid incapacitation and vomiting (and possibly choking) is worth -10 points (see Motion Sickness, Free Sick, and Space Sickness).

The value of Timesickness and immunity to it will change depending on default time travel effects set by the GM.

Using these guidelines, you can develop sicknesses stemming from other sources – hyperspace travel, strong magnetic fields, etc. A simple -3 HT penalty to avoid some normal bad effect might be worth only -2 points (though GURPS awards Acceleration Weakness -5 points, presumably for fighter jock campaigns).


GURPS offers Acceleration Tolerance and Immunity to Timesickness, but lacks counterparts for a couple other weaknesses. If you like, invent a Space Sickness Tolerance: 1 point per +1 on rolls to avoid sickness and choking, up to 10 points for absolute immunity. Free Sick Tolerance would work similarly.

And while typical vehicle rides cause no trouble for normal people, anyone may need to roll against HT to keep from summoning lunch while on camelback, a runaway roller coaster, or a storm-tossed ship. For stronger stomachs, build a Motion Sickness Tolerance as above but at half cost – sickness rolls for Earthbound PCs won't come as often as they do for spacers, and the sickness won't usually be as deadly.

Improved G-Tolerance and G-Intolerance deal with resisting the effects of unusual gravity.

Motion and Gravity Tolerance options: HT; acceleration options (Acceleration Tolerance; Acceleration Weakness); motion options (Motion Tolerance; Motion Sickness); gravity options (Improved G-Tolerance; G-Intolerance; Free Sick/Space Sickness Tolerance; Free Sick/Space Sickness); time travel options (Immunity to Timesickness; Timesickness).

Pressure and Altitude Tolerance

Pressure's no fun, but a lack of it can hurt too! Effects of high pressure are detailed on CII p. 144, and vacuum on p. 149.

Choose your native pressure level; this is worth no points, no matter how extreme it is. For humans, native pressure is 1 atmosphere. Underwater, pressure increases by 1 atmosphere every 10 yards down (in Earth gravity).

Pressure Support (revised)

1 point/level

Like Temperature Tolerance and the local temperature, Pressure Support extends your "native" pressure comfort range in either direction.

Each level of Pressure Support in the high direction lets you handle additional pressure using the progression x2, x3, x5, x7, x10, x20, x30, x50, x70, x100, etc. 5 points lets you handle 10 times native pressure, 10 points 100 times, and so on.

Pressure Support in the low direction uses the above multipliers as divisors, but 5 levels beyond support for 1 atmosphere lets you handle any pressure down to vacuum, removing the dangers of explosive decompression in space. (The cold and lack of air are totally separate problems!)

Example: A spacefaring humanoid might have 5 levels of low Pressure Support, allowing safety in vacuum. A seafaring humanoid might have 5 or more levels in high Pressure Support for deep dives.

Example: A fish in the deepest part of the sea might have 1000(!) atmospheres as its native pressure. That's worth nothing, but if it can also travel to the surface without ill effects, that'd be worth 15 points. (Unfortunately, most deep-sea fishies seem to have invested their points elsewhere... pop!)

Respiration: Assume Pressure Support lets you inhale and exhale in atmospheres of the appropriate pressure, if there is anything to breathe. For a human, two levels in the high pressure direction allows breathing in dense atmospheres, four levels in very dense. Superdense atmospheres will require at least five levels.

Low Pressure Support is useful even on Earth for climbers or fliers. Let each level add 3000 feet to altitude ceiling (CII p. 132) and confer +2 on HT rolls to prevent altitude sickness. Two levels allow breathing in thin atmospheres, four levels in trace atmospheres. But even with five levels, Earth birds hit a ceiling above 30,000 feet where there's not atmosphere for breathing and flying. (For fliers, you might want to rename the trait Altitude Support.)

But in all cases, just because you can physically inhale and exhale normally doesn't mean an exotic atmosphere isn't poison to you, or that a thin one offers enough oxygen to keep you alive! See Reduced Air Requirements for help here.

Vacuum Support (revised)

varies (package)

Put together an appropriate package of traits to survive in vacuum; this replaces both the Vacuum Support and Vacuum Adaptation advantages in GURPS.

Unless you bring along external air or have long-lasting internal stores, true Doesn't Breathe [25] is a must. Pressure Support for vacuum is also essential [5 if you can handle Earth atmosphere as well, or 0 if you can only handle vacuum]. You don't really need high Pressure Support unless you plan to buzz dense atmospheres.

Take at least 10 levels of Temperature Tolerance against cold [10], or set your comfort zone way down toward the Kelvin zero region. Take lots of Radiation Tolerance – the more the better, but 10 levels is a good start [10].

Those are the basics, worth 50 points (55 with the additional Pressure Support). You'll probably want to add some sort of vacuum mobility, and maybe some DR to simulate a toughened hide.

Pressure and Altitude Tolerance options: normal; Pressure Support; Vacuum Support.

Regeneration and Recovery

HT handles the basics nicely, while additional traits run the gamut from improved healing to out-and-out return from the dead!

A quick suggestion for Rapid Healing and Very Rapid Healing: let the former add +5 to healing rolls and the latter +10. Let success by 10+ points on the HT roll heal 2 points of damage, success by 20+ points heal 3 points, etc.

Regeneration and Recovery options: HT; Slow Healing; Rapid Healing; Very Rapid Healing; Recovery; Regeneration (Slow; Regular; Fast; Instant); Regrowth; Resurrection.

Sleep Requirements and Disorders

Sleep is included under Health and Resilience as it's a "recovery period" required by the body for... well, we're not exactly sure yet what it's for, but we like it all the same.

If you're diurnal you're active by day, and if nocturnal you're up and about by night. This is by preference or instinct. Either is a 0-point effect.

Nocturnal (capitalized) is a game trait that shuts down your body and mind by day! Feel free to invent a Diurnal counterpart.

Less Sleep and Extra Sleep affect how many hours of shuteye you need per night, and are appropriate for individual characters. Reduced Sleep and Doesn't Sleep are definitely nonhuman, and Sleepy is useful for creatures that sleep more than humans (like cats) or need to shut down for extended periods (like hibernating creatures).

Traits affecting quality of sleep are included here too. Deep Sleeper lets you wake up refreshed; Light Sleeper and Insomniac will make you red-eyed and grouchy. If you have Sleepwalker, don't sleep nude and don't camp by a cliff...

Catsleep: A useful trait:

Catsleep (new)

5 points

You can fall asleep easily when you want to, but your brain sleeps one hemisphere at a time or otherwise maintains a degree of alertness. You can make sense rolls to detect dangers other sleepers would miss (though at -2 compared with being awake), and don't suffer mental stun upon awakening.

You can even choose one continuous activity that requires no significant power or concentration while sleeping. Sharks keep swimming while asleep, seals and dolphins surface periodically to breathe, horses stand, and ducks float with one eye open.

If you want to combine several "autopilot" activities, pay an extra 2 points per activity over the first.

Catsleep combines some features of both Deep Sleeper and Light Sleeper; you may be jarred out of sleep more than usual, but without as much overreaction as Light Sleeper.

Sleep Requirement and Disorder options: behavior (nocturnal; diurnal); exotic behavior (Nocturnal; Diurnal); individual sleep requirements (Less Sleep; Extra Sleep); racial sleep requirements (Doesn't Sleep; Reduced Sleep; Sleepy); sleep quality (Deep Sleeper; Light Sleeper; Catsleep); disorders (Insomniac; Sleepwalker).

Miscellaneous Systemic Flaws

Some of the below are unlikely traits in species but work fine in non-species designs:

Miscellaneous Systemic Flaws options: none; low HT or other stats; Epilepsy; Hemophilia; Migraines; Vulnerability; Weakness.

Agility and Flexibility

Reflexes, overall coordination, and manual coordination are overlapping areas covered by DX, with some mental component as well. Skeletal flexibility is a purely physical condition.

Manual coordination is covered under Manipulators.


DX is the big factor here; set as you like. If you're using the natural encumbrance rules, don't go overboard in assigning high DX to small creatures and low DX to big creatures; natural encumbrance will do a better job of giving you the effect you're looking for.


Catfall subtracts 5 yards from effective falling distance, and lets you halve any damage on a DX roll. If you determine falling damage from velocity (per Book 6 rules), not height, let Catfall subtract 20 mph from velocity instead.

In real felines the trait is a spread-legged pose that slows the fall and lets the legs act as shock absorbers, coupled with a limp body to disperse the shock. It isn't just for cats, either – mice reportedly use the same technique, and a hedgehog's spines absorb impact shock.

Allow a +20% enhancement to Catfall: No Conscious Control Needed. The advantage works even if you're knocked out!

Really small creatures will be effectively immune to falling damage. This is a benefit of their light weight and slow terminal velocity, not reflexes; no Catfall necessary! See Book 6 for more on falling.


A new reflex-related option:

Reduced Dodge (new)

-5 points/level

You dodge poorly, possibly because of slow reflexes or poor mobility. Each level reduces Dodge by 1. Reduced Dodge affects your land, water and air mobility equally, and is useful for building physical conditions that include mobility penalties.

The maximum number of levels you can buy is as many as take Dodge to 0, or 5 levels, at which point the Rule of -5 gives you No Dodge. You lose all Dodge ability and have to rely on Parries, Blocks, and durability alone.

Reflexes options: DX; Combat Reflexes; Combat Paralysis; Increased Speed; Reduced Dodge; Catfall; Hyper-Reflexes.


Coordination traits deal with precise and independent positioning of body parts, though there's no clear break from Reflexes traits. See Book 4 for more on balance.

Some new items:

Improved Balance (new)

2 points/level

This is a generic bonus on balance rolls, including all rolls to maintain balance or footing, recover from failed kicks, etc.

Improved Balance can come from appendages to aid balance (often a tail, though wings or other appendages could work), from multiple limbs (included in the Extra Legs advantage) or a low center of gravity (appropriate for a short-legged or no-legged creature).

Bonuses related to appendages are lost completely if the appendages are crippled or hampered. Also halve the bonus (round down) if you tumble or otherwise lose contact with the ground.

Enhancement: Your Improved Balance comes from an internal sense of positioning and is not reduced by injuries or loss of footing. +50%.

Poor Balance (new)

-5 points/level (max 5 levels)

Each level of this land-specific disadvantage reduces athletic rolls by 1 (half this penalty, rounded down, on defenses) and balance rolls by twice as much, and further adds a level of Poor Kicker.

Simply making an athletic action can create a risk of falling (see Book 4). Start with a balance roll at +10, with all appropriate balance modifiers (including that for Poor Balance itself). If that's 15 or higher, don't bother rolling. Otherwise, roll: failure is a fall immediately after the action (or possibly off-balance, using Book 4 rules).

Even a semi-athletic action like walking requires a check vs balance +12 to avoid falling, using the same procedure; simply standing requires a check vs balance +14.

Kicks can be disastrous. The athletic skill penalty, combined with Poor Kicker, on top of a kick's -2 DX, means the kick is likely to miss. The above balance roll after any athletic action, with penalties for an attack, for a miss, for only one leg on the ground, and for Poor Balance, almost guarantee a fall.

Effects of Poor Balance can often (GM call) be halved by kneeling, or negated by sitting or lying down. Poor Balance is also useful to game the effects of drunkenness or some diseases.

Partial Coordination (new)


This is the opposite of Full Coordination, which lets you fully coordinate actions using three or more arms. Partial Coordination means you have trouble coordinating even two arms (or any limbs used for purposes other than movement). You perform normally with one arm, but take a -1 DX on any actions using two (climbing, catching a beach ball, two-handed sword use), and -2 DX on any two-handed tasks of fine motor skill (most craft, musical instrument, and repair tasks).

Partial Coordination is a -33% limitation on the cost of your second manipulator, which under later rules means -5 points for a normal human.

Coordination options: DX; handedness (right; left; Ambidexterity); coordinated limb use (Partial Coordination; normal; Full Coordination); Klutz; balance (Poor Balance; normal; Improved Balance; Perfect Balance).


DX plays the lead, but traits add a lot more flexibility. GURPS says nothing on the combat benefits of Double-Jointed, Flexibility, etc.; suggestions below are GULLIVER's.

Flexibility traits should not confer bonuses on Mechanic or similar skills! Mechanic is a knowledge skill, and couldn't possibly be improved by rubbery arms. However, mechanical repairs and similar tasks are often hampered by cramped work spaces – and here flexibility should reduce skill penalties for tight quarters.

Example: A star drive compartment is tightly packed with machinery: a -4 penalty to perform repairs. However, the ship's Double-Jointed Zorxx mechanic removes 3 from the penalty, for a -1. The rubbery Aeoil engineer with Flexibility removes up to 5 from the penalty, and so is unhampered.


Inflexible Body: A useful trait for many animals:

Inflexible Body (new)

varies (package)

Your body, and especially waist or back, are inflexible. Your limbs articulate, but may have trouble reaching far parts of the body, like turtles, crabs, and beetles. DX and negative encumbrance should be limited.

Customize your condition using the following:

Reduced Dodge: Take one level [-5].

General Inflexibility: Take a -2 on Acrobatics, Jumping, Swimming, Dancing, Escape, Climbing, most Sports skills, martial arts requiring exceptional mobility (basically, all those taking penalties for encumbrance), and attempts to break free from a pin [-5, or -3 for half this penalty].

Stiff Limb Articulation: Attacks or defenses requiring unusual positioning (GM call, but may include Wild Swings, kicks to a given direction, Parries to side hexes, etc.) suffer an additional -2 penalty. Attempts to resist or break out of an Arm Lock are at -2. Scratching your back is hard or impossible, and if you walk with a straight-legged stance, crouching or crawling is very difficult [-1].

Stiff Neck: Your neck turns little or not at all. You have to turn your body around to look behind you. Your bites and head butts can only attack your front hex [-1].

Stiff Back: Your waist doesn't bend, resulting in many minor nuisances – in particular, a -2 on Acrobatics [-1].

Difficulty Standing: "I've fallen and I can't get up!" To get up from a nap or after a fall, make a DX roll (add your Half modifier for encumbrance) to gain your footing before you can take the Change Position maneuver [-2].

Optionally, you're in even more trouble when on your back: you need to first make a DX roll just to turn onto your side! This is at -2 for Stiff Limb Articulation (above), -2 for each level of combined Short Arms and Short Legs, +2 for a High Stance, -2 for a Very Low Stance (below). After that you start making DX rolls as above, and can then take Change Position to stand. [Additional -1]

Total cost: The "standard" package combines Reduced Dodge, full General Inflexibility, all "stiffnesses", and basic Difficulty Standing, for -15 points. (Note total -4 on Acrobatics.)

Many large herbivores have Difficulty Standing [-2] and possibly Stiff Limb Articulation [-1] (cow-tipping, anyone?). Turtles have the full -15 points, but replace Stiff Neck with the extra difficulty getting off their backs. A belly-up tortoise with DX 6 and Short Legs isn't going anywhere.

Changing position: The following modifies time to make position changes, and in general is only meaningful on land:

Fast/Slow Change Position (new)


You make Change Position maneuvers particularly quickly or slowly:

Fast Change Position: 2 points halves the time needed for one specific Change Position maneuver (which may take several seconds if you have lots of encumbrance); 5 points halves the time for any and all.

Slow Change Position: Every -1 point doubles the time needed for all Change Position maneuvers; at -5 points, the Rule of -5 multiplies time required by sixty! Modify these costs for special circumstances as you see fit.

Note also Difficulty Standing under Inflexible Body above.

Flexibility traits

Most of the below should look familiar. Small races and people are more likely than large ones to have them.

Double-Jointed (revised)

5 points

Effects are per BS p. 20, with the exception of the Mechanic skill bonus: Double-Jointed only reduces penalties for working in cramped spaces, by up to 3.

Double-Jointed confers a +1 to resist or Break Free from a pin, and a +2 to resist Arm Locks and the pain or damage from a lock. The Active Defense penalty for a double-jointed character in an Arm Lock is only -3.

Extra Flexibility (revised)

5 or 10 points

Cost is 5 points for a single limb (like an elephant's trunk), or 10 points for the whole body. Limbs can reach any part of the body (as length allows), regardless of body position or layout; an arm can defend or attack left and right flanks with equal ease.

GURPS' trait offers no benefit beyond the above and appears less useful than Double-Jointed. Let the trait include Double-Jointed (whole-body or one limb), and let whole-body (or neck only) Extra Flexibility add the ability to turn your head 180° to the rear.

Flexibility (revised)

15 points

Flexibility is beefed-up Double-Jointed (which cannot be combined). Despite the confusing name, it's also better than Extra Flexibility. (If you want to clear this up, give Flexibility the new name Super Flexibility, and save the single word "flexibility" for generic use.)

Your body and limbs bend in any direction. Effects are per the BS, though unusual stretching or squeezing is not possible. Penalties on Mechanic or other skills for cramped conditions are reduced by up to 5. You can put your neck through a full 360° turn!

Flexibility gives a +2 bonus on any attempt to Break Free or to resist a pin, and a +4 bonus in the Contest to avoid an Arm Lock or resist its pain/damage. Your Active Defense penalty in an Arm Lock is only -2. Take a +1 to Acrobatics.

Squishy (new)

5 points

"Malleable" is another good name for this advantage: you're boneless, or have bones that slip and dislocate easily. (If the former, add the 0-point effects from Invertebrate.) You can squeeze your body in unusual ways, even forcing your head through an opening half its girth!

Double-Jointed, Extra Flexibility, or Flexibility is a prerequisite for Squishy. You get the benefits of the prerequisite with an additional +2 on Escape, and +1 to break free from a pin or resist an Arm Lock and its effects.

Squishy lets you to stretch slowly – not far or quick enough to be of use in combat, but by HTx2% or so, little by little. But Squishy is not a quick shape-change ability; any unusual squeezes or stretches take a minute or two, halved on a DX roll or a DX-based (P/A) version of the Change Control skill. Examples include soft invertebrates and Tooms from The X-Files.


Stretching includes Flexibility; let it include Squishy too, combining Squishy's "rubberiness" with quick and extreme stretching ability. However, the -50% Stretching limitation "Does Not Include Flexibility" removes both Flexibility and Squishy from the advantage.

Stretching allows great combat Reach for a cost much lower than Increased Reach for all limbs. If this is a problem, raise the cost of Stretching by 10 points or more per level.

Flexible hierarchy

The above places flexibility-related traits into a "hierarchy":

Bouncing, Invertebrate, and Constriction Attack are yet more flexibility-related advantages. The latter is an expensive ability with Extra Flexibility as a prerequisite, but doesn't offer much advantage over strangling. Book 5 has improved choking and constriction rules.

Flexible Neck

If you have a neck, let it turn up to a full 180° for 1 point, up to 360° for 2 points, and spin freely for 3 points. These levels give you +3, +6, and invulnerability, respectively, when resisting the Neck Snap maneuver, but confer no other benefits of No Vulnerability: Neck.

Let Extra Flexibility include one level of Flexible Neck, and Flexibility (or Stretching) confer two levels. The third level is obviously unnatural, but would be appropriate for a robot with a free-spinning neck.

Flexibility options: DX; Inflexible Body; modified change position (Fast Change Position; Slow Change Position); Double-Jointed; Extra Flexibility (One Limb); Extra Flexibility (whole body); Flexibility; Squishy; Stretching; Bouncing; Constriction Attack; Flexible Neck.

Life Cycle

Unique maturation and reproductive cycles add fascinating "color" without big point cost adjustments. But even an overview of the variety found in nature would overwhelm this document, so consult a biology book for ideas. Below are only relevant game traits and a few general choices. For a totally new life cycle system, see the Life Span Meta-system in Book X.

Point costs related to reproduction and lifespan only matter in an extended campaign. For a one-shot or a short campaign, these traits should be no more than quirks!


As a counterpart to GURPS' Early Maturation trait, let Late Maturation increase the time it takes to reach adulthood for -1 point per level. This covers physical maturity only; maturity as viewed by society is handled by the Youth disadvantage.

Immature creatures can have a totally different form from the mature form, or even pass through several forms. Describe any moltings, cocoonings etc. that led to your current design.

Model ongoing changes appropriately. If a PC spends 10% of his time with no DR and a couple levels of Reduced Move because of molting, the disadvantage value is 10% of the value of those troubles – if the changes happen more or less without warning. If they happen according to a schedule, halve the disadvantage value; the PC can plan ahead for safety during those times. In short, temporary changes won't likely be more than a quirk.

If you reach an age where ongoing changes stop, buy them off.

Maturation options: normal; modified maturation (Early Maturation; Late Maturation); modified maturation and life span (Extended Lifespan; Short Lifespan); various metamorphoses.

Gender and Reproduction

Eunuch is a combination of Sterile and social problems best suited for individual use. A race can't have Sterile unless it procreates through technological means. Complexly colonial creatures may have select individuals specializing in reproduction, with the remaining majority sterile.

Assuming you do have your equipment intact, you can send off buds, shoots, spores, or seeds, or even commit mitosis and split into two. You can be viviparous (giving live birth), oviparous (laying eggs), or ovoviviparous (holding eggs in the body). Or you can take the easy route and just be male.


Species employ reproductive strategies. Do you release thousands of eggs or spawn, hoping a handful will survive? Or do you carefully nurture a few young to self-sufficiency? Creatures with a litter can respond with cold behavior ranging from simple indifference to the infamous "eats own young". Others take care of their brood, gaining Dependents, Sense of Duty (own or race's children), and a renewed acquaintance with poverty. Not surprisingly, the degree to which the parents care for offspring is usually tied to inability of the young to care for themselves.

These are among the most important "real-life" traits of all to a species! But reproduction has little effect on PCs, and so the traits are worth few or no points.

Gender differences

A gender can have unique traits, including ones that manifest only at certain times in the reproductive cycle. Price the latter using the notes on ongoing changes under Maturation.

Sexual dimorphism refers to differences in form among genders – color, plumage, size, you name it. Human males are bigger than females, but the reverse is true for many species. Some fish and mollusks take size dimorphism to the extreme, with the male attaching itself to the female and shriveling away to a tiny sperm-producing appendage. In game terms, the male's not even a "character", just the female's cure for Sterile! (Insert your own wry jab at mankind here.)

Gender-based traits in humans are up to you. Weight and ST differences are very real, but you don't have to hand out a "ST gender bonus" to male PCs. Start PCs with the same goods regardless of gender, and just nudge the players of strapping male PCs to take decent ST, or ask the player of the five-foot-three female PC for a story to explain her ST 14. But it's a game, so don't worry about it much!

Bio-Tech mentions a lack of testicles as a debilitating combat target in females [2], as well as menstruation [an implied -1]. The book also offers Altered Sex Ratio, Estrus, Extended Fertility, Increased Fertility, Light or No Menses, Reproductive Control, Sexual Orientation, Shorter Gestation, Easy Childbirth, Parthenogenesis, and Exotic Genitalia.

Gender & Reproduction options: reproductive means (sexual; asexual; Parthenogenesis); gender (male; female; Hermaphromorph; other); gender-specific traits (Estrus; Light or No Menses; other); fertility (Sterile; Eunuch; Dying Race; normal; Extended Fertility; Increased Fertility; Reproductive Control) gestation and delivery (live birth; Shorter Gestation; Easy Childbirth; seeding/egg-laying; budding; other); others (Altered Sex Ratio; Sexual Orientation; Exotic Genitalia).

Life Span

Extended Lifespan and Short Lifespan are natural racial traits, while GURPS suggests a variant of the former, Longevity, for humans. Short Lifespan and Accelerated Aging are exactly the same thing. Undying and Immortality are package advantages that include Unaging.

Youth and Age also determine how much time an individual (not a race) has left before the end. (Youth is really a form of Social Stigma related to legal status and perceived social maturity, not actual physical maturity.) Terminally Ill or Self-Destruct bring the end sooner; the latter is very suitable as a racial disadvantage.

Default life span

For cost purposes, human life span is always the default. Buy whatever traits you need to get actual life span.

There have been studies equating size and metabolic rate to life span in animals, suggesting a likely span for your design. See Book 6 for details.

Life span options: normal; individual age (Youth; Age); individual life span (Longevity; Accelerated Aging); racial life span (Extended Lifespan; Short Lifespan); exotic life span (Unaging; Undying; Immortality); disorders (Terminally Ill; Self-Destruct).

Mobility Meta-stuff

Below are rules for mobility that offer new design flexibility and detail. They include revised rules for design of legs and wings and other appendages for getting round, yet these don't stray too far from GURPS rules. For a single, more technically spiffy set of rules for designing legs, arms, manipulators, wings, and any wacky combination thereof, see the Appendage Builder System in Book X instead.

Environment and Mobility-related Disadvantages

There are lots of ways to get around, but these can be grouped into three big "modes of movement", using the same names as the Environments they represent: land, water, and air.

Primary Environment

See Overlapping Disadvantages above for a treatment of mobility-related disadvantages. For your primary Environment, all mobility-related disadvantages should not total more than -80% the value of your mobility, or -100% if you're truly immobile. Assume "free" default mobility itself starts with a value of 50 points (the value of the Sessile disadvantage).

Example: Your terrestrial race pays 25 points for two levels of Enhanced Move and Sure Footing, but you personally suffer severe mobility limitations. The most you receive for all related disadvantages is (50 for mobility + 25 for enhancements = 75), -80% = -60 points, or a full -75 points if you really have no land mobility whatsoever.

The same applies to the default air mobility and added flight traits of true aerial creatures.

Non-primary Environment

Mobility in non-primary Environments starts out bad, but can be made worse with poor encumbrance, Reduced Dodge, Reduced Move, Incompetence, etc. You can even have Lame – that's the difference between a lobster or octopus on land, clumsy but mobile, and a beached dolphin, just lying there with no legs.

Disadvantages only have x1/5 value, however. So does your "free" default mobility, reducing its value to 10 points!

Example: A whale doesn't even have default poor mobility on land; it's truly immobile. The most points it can receive for No Legs (land only) and terrible encumbrance is -10 points.

Example: Your terrestrial race has water mobility-related advantages worth 20 points: possibly two levels of Enhanced Move, or Amphibious and Enhanced Move. However, your PC suffers severe swimming problems. The most you receive for all related disadvantages is (10 for mobility + 20 for enhancements), -80% = -24 points. Make that the full -30 points if you have no water mobility whatsoever.

A non-aerial creature has no "free" default mobility, so the maximum value of flight-related disadvantages is -80% the value of flight-related advantages, i.e., -32 points if you have 40 points in advantages (say, Powered Flight [30] and improved natural encumbrance in air [10]).

Speed-related Traits

Some traits affect only one mode of movement (like Enhanced Move, or various Super movement powers); others affect you regardless of mode (Reduced Dodge or natural encumbrance).

Top speed

Your Move score equates to "top speed", with a boost possible through sprinting. Take a -1 point No Sprint disadvantage for a mode of movement in which you cannot sprint.


Enhanced Move comes in land, water and air versions, each bought separately. Each level adds 100% to base Move. Super Running, Super Swimming, and Super Flight are more powerful: each level doubles Move.

Hyper Sprint: A new trait:

Hyper Sprint (Environment) (new)

7 points/level

This is Enhanced Move with a -30% limitation: Sprinting Only, and replaces the usual Sprint bonus. A creature with Move 7 and a level of Hyper Sprint would have Sprint Move 14; with two levels, Sprint Move 21. Buy Hyper Sprint separately for land, water and air movement.

The drawback is the fatigue and other penalties for sprinting; see Book 4.

The advantage is appropriate for creatures like cheetahs and crocodiles that can put on great bursts of speed, but for short periods only.

Reduced Move: A reworking of this common trait:

Reduced Move (Environment) (revised)

-5 points/level

Each level reduces your Move as if you were one Size level smaller. Take Reduced Move separately for land, water, and air movement.

Dodge is not affected by default; combine with Reduced Dodge if you like.

At 5 levels the Rule of -5 kicks in: your Move drops to a mere x1/10.


Acceleration and deceleration are generally ignored in GURPS. You can automatically move your full Move from a dead start, with one extra second needed to reach sprint speeds, and stop as you like.

Book 4 offers acceleration and deceleration suggestions. To summarize here, your size and encumbrance affect acceleration, deceleration, and top speed, while Enhanced/Reduced Move affect only top speed. Add +10% to the value of Enhanced/Reduced/Super Move if it does affect acceleration, and +10% if it affects deceleration.


Add Reduced Move to represent poor streamlining – but it's only warranted if you move fast (relative to your size) to start with. What's fast is up to you.

If you insist on playing with drag and streamlining, see Books 1 and 4. for terminal velocity and detailed suggestions for drag and Move. Notes below on surface area are for use with those rules.

Cost of drag effects: Default terminal velocity has no point cost. An insect-like PC will enjoy a wonderfully safe falling speed, for free. The same for wings: the slowdown they provide in your falling speed is a free benefit.

A slower falling speed from any other factor, though, costs points. This includes natural parachutes, static lift, airfoils, and wings that do nothing but slow falls. See Slow Fall.

In the forward direction, there's no point value for good or poor streamlining; the points are in the Reduced Move that you do or don't buy.

Speed-related traits options: No Sprint (Environment); Reduced Move (Environment); Hyper Sprint (Environment); Enhanced Move (Environment); super move (Super Running; Super Swimming; Super Flight; Hyperflight); drag effects.

Other Mobility Traits

Motive power

Motive power on land comes from Load ST. In air or water, it's thrust. This is also the same as Load ST by default, but can be set arbitrarily lower or higher. The cost is only that of final natural encumbrance.

Encumbrance level

Book 2 has rules for determining and pricing encumbrance separately on land, in air, and in water.

Directional movement cost

You have six "hexes" around you for game purposes: frontmost, front right, front left, side right, side left, and rear. By default, you can move into the front three for one point of Move, and the remaining three for two points of Move.

For variety, you can rearrange these at no cost – say, reversing the costs for forward and backward movement.

You can also increase the cost to enter any one hex, a -1 point disadvantage per extra Move point required. Let the max cost to enter a hex be 5; for one more point of disadvantage, you can't enter that hex at all! (Thus, you get -5 points for "blanking out" a front hex, -4 for a side or back hex.)

Example: Emu and kangaroos cannot walk backwards (or so say the designers of the Australian flag). "Blanking out" rear and side hexes is worth -12 points. No retreat, no dishonor!

To reduce the cost to enter a hex from two Move points to one (and no lower), pay 2 points. So for 6 points you run backwards and sideways as fast as you run forward – like a level of Enhanced Move with a -40% "rear three hexes only" limitation. This doesn't necessarily mean you can see where you're going!

Example: You're a side-scuttling crab. You rearrange your movement costs so your frontmost and rearmost hexes require two Move points, and the remaining four hexes require only one Move point. The rearrangement itself costs nothing, but now only two, not the default three, of your hexes require two Move points to enter. This costs you 2 points.

Adjustments are for one mode of movement only; rearrange hexes and their movement costs separately for other modes of movement, as you like.

Swimmers: No backward movement is the default underwater, except for very slow swimming (x1/5 Move or so). If you can move backward normally, buy the advantage based on the above disadvantage costs!

Many swimmers reverse backward and forward in water [0]: lobsters, shrimp, squid, etc.

Fliers: For fliers, use a limitation on the cost of flight traits instead. It'll always be tied to the Cannot Hover limitation. For simplicity, let Cannot Hover be worth the usual -15%, and the combination Cannot Hover/Move Backward be worth -20%.

Inaccessible Propulsion

Here's an interesting advantage:

Inaccessible Propulsion (Environment) (new)

5 or 10 points

Your mobility relies on propulsors that can't be easily injured or hampered, making it hard for foes or accidents to stop you. (You still slow down from overall HP loss, in the usual manner.)

Purchase Inaccessible Propulsion separately for land, water, and air mobility.

For 10 points you have no propulsors that can be hampered or injured. Mobility may come from magic, jets, or torso movements – a foe would have to cripple or tie up your body to stop you, and that'd take you out of action anyway. Perhaps you telekinetically glide a yard over the ground for Inaccessible Propulsion (land), or fly on "wings of hope" for Inaccessible Propulsion (air).

For 5 points, loss of your propulsors (legs, swimmers, or wings) affects mobility half as much as it would otherwise; you maintain half Move even after losing all propulsors, with other appropriate penalties on actions. A snake or fish, still able to move slowly with body movements if the "tail" (a Single Leg) is lost, is a good example. Use Crippled Leg effects as a guide for the loss of all legs; water and air effects are detailed later.

You can tweak the effects for swimmers and fliers: instead of half normal effects, loss of propulsors with Inaccessible Propulsion [5] might have full effects on speed of movement but no effects on maneuverability. Or vice versa.

Reduce or remove the point value of traits changed by Inaccessible Propulsion. Lame will be worth little or none if it has no effect. Traits like Enhanced/Reduced Move, Improved Balance, Poor Kicker, Poor Jumper, etc. which still have their normal effect on you are valid purchases.

Other mobility traits options: aquatic and aerial thrust; encumbrance level; buoyancy; Variable Buoyancy; directional movement adjustments (rearranged hex Move costs; increased or decreased hex Move costs); Inaccessible Propulsion (Environment); primary and home modes of movement (land, water, and/or air)

Land Mobility

Below are traits affecting your mobility on land.

Number of Legs

Call whatever you use to move on land – legs, belly, tail, whatever – walkers. Their most important function is mobility, worth a "free" 30 points for a terrestrial creature, as mentioned earlier. For a human, the default two legs confer propulsion. (Pricing each leg here isn't very meaningful; a missing leg is almost as bad as no legs.)

You can also kick with your walkers by default. A leg acts as a striker [10 points with a one-hex Reach], but it's not a good one: -2 DX, and probably even worse at armlike swings or throws (if it had manipulators to begin with). Halve cost. And unlike a dedicated striker, standing and striking at the same time is tough – you can fall if you miss a kick. Halve cost again. That leaves a "kicker" worth 2.5 points, and the default two worth 5 points.

So the default two legs are worth 30 points as walkers and 5 points as strikers, for 35 points.

Missing and defective legs

If you have no legs and can't move, take Sessile (you're glued in place), Paraplegic (you can move using arms) or Quadriplegic (you have no functioning arms or legs). If you have one leg (or a mixture of good and bad legs), take Lame.

Lame is reworked below, with multipliers for Move (instead of subtractions) and DX penalties for combat actions based on Poor Balance. (The One Leg combat penalty shouldn't be -6 DX when the combat penalty for actually sitting down is only -2!) Costs are loosely based on this combination, or a bit less, as Lame can be somewhat ameliorated by simple aids.

Point costs may differ from GURPS: Crippled Leg is given a -20 point value and One Leg a -30. Even with these higher values, Lame presents serious penalties and is hardly a bargain.

Lame (revised, new cost)


You have crippled or missing legs. The names are only descriptive: Crippled Foot could be a damaged knee, or Crippled Leg a missing foot.

Seated or in a wheeled platform, Dodge, athletic, and balance rolls will be at -2 or be impossible, as appropriate. If you power your platform by hand, Move will be x1/2 at best (and the platform's mass adds to overall mass).

Quadriplegic is a combination of No Legs and No Arms (below), for -75 points. Use the -80 cost if you have no crude manipulators whatsoever to fall back on (not even strikers, wings, etc.); this would be the case with humans.




Poor Balance

other effects

Bad Foot



1 level

Crippled Foot



1 level

Bad Leg



2 levels

Crippled Leg



2 levels

Bad Legs



3 levels

One Leg



3 levels

No Kick

No Legs



can only sit/lie

No Kick




can only sit/lie

No Kick, No Arms

Move: Modifies both Move and jumping distances.

Poor Balance: Levels of the Poor Balance trait conferred by Lame. Each level reduces athletic rolls by 1, balance rolls by twice as much, further adds a level of Poor Kicker, and creates a risk of falling after any athletic action.

Advanced rule: Use only x2/3 Load ST when computing encumbrance with Crippled Leg or worse, as there's less strength available for support and mobility. Additional natural encumbrance will carry its own disadvantage value.

Prosthetics: Prosthetics will reduce the severity of your condition and its cost. A crutch or TL 5- prosthetic reduces the penalties of One Leg or better by one level. A TL6 or 7 prosthetic will reduce the severity of One Leg or better by two levels. TL8+ prosthetics can be as good as or better than a real leg, negating disadvantage.

For more detail, borrow the correctable disability rules from Senses: your disadvantage level is between the corrected and uncorrected state. A troublesome, droppable measure like a crutch is equivalent to glasses or contacts (x2/5 value); a prosthetic leg that normally stays put is like a modern hearing aid (x1/5 value).

Example: You have One Leg. With a crutch, the cost of your condition is x2/5 the way from the corrected state [-25] to the uncorrected [-30], or -27 points. With a modern prosthesis, the cost of your your condition is x1/5 the way from the corrected state [-20] to the uncorrected [-30], or -22.

A good-as-new bionic leg is worth no extra points over the corrected state [0] if it's trouble-free. But if requires power, can be pulled off, etc., use x1/5 the way from [0] to [-30], or a -6 point disadvantage.

Other generic leg abnormalities can be built with Reduced Move, Poor Jumper, etc.

Legless movement

Single Leg: Lame (One Leg) is clumsy and unbalancing, but a species that's supposed to have only one propulsor – snake, clam, fish, etc. – is another matter:

Single Leg (new)

0 points

You have one single leg or other propulsor, offering the support and mobility of regular legs. Treat as two normal legs for control and other purposes.

As a Single Leg lacks a "backup", injury can be particularly crippling. As compensation, it's usually thick and strong; use x2/3 total HP (round up) for its HP, instead of usual leg HP. These special effects balance to 0 points.

A Single Leg is likely to have some functional drawbacks. Add No Kick, No Jump (or Poor Jumper), Poor Climber, Reduced Move, etc. as appropriate. If the Single Leg is difficult or impossible to clothe or armor, add Inconvenient Form.

You have no balance adjustments by default, but see Posture above.

Other features: Part of snakes' movement comes from the torso itself; see Inaccessible Propulsion above.

How much of your snaky body is on the ground, and how much is in the air, is determined by your posture. Also see notes on rearing up below.

Extra Legs

The below revises Extra Legs and raises cost. A couple of Extra Legs gives you more strikers, better stability, and backups against injury. Your default two legs are "back" legs; additional legs are "front" ones. You can "rear up" on your back legs to push or kick with the front ones. "Rearing up" on front legs is a difficult or impossible acrobatic feat for most creatures.

Extra Legs (revised)

1.5 points each plus Striker ability

You have three or more legs. These "backups" lessen the effect of leg injuries. Half of your legs act as one human leg. With four legs, treat one crippled leg as Crippled Foot, and one missing leg as Bad Leg. Treat two crippled legs as Crippled Leg, and two missing legs as One Leg. With six legs, treat three crippled legs as Crippled Leg, three missing legs as One Leg, and so on.

Basic cost: Extra Legs cost 1.5 points each for their value as walkers. Striker ability costs 5 points each, reduced as below. Add these together to get leg cost.

Reduced cost: Buy the first two Extra Legs at full cost. Multiply cost for the next two by x1/2, the next four by x1/4, the next eight by x1/8, the next eight by x1/16, the next eight by x1/32...

Limit on number: There's no limit on how many legs you can have, other than crowding. Short Legs and Reduced Move may be appropriate for a very large number oflegs.

Balance: Extra Legs includes free Improved Balance, based on the total number of legs on the ground. Legs that are crippled, raised up, or otherwise hampered don't help!

Other: The additional power and balance from Extra Legs can also help in Contests of grappling, pinning, pushing, etc.; see Book 5.

Rearing ability: Adjust cost of legs' striking (not walking) ability for the following:

Some differences between your reared position and actual crippling: you can kick with the raised legs, at only the normal -2 DX kicking penalty; these kicks do not force the usual GURPS falling roll if they miss. Rather, you'll have to make a balance roll to avoid falling after any athletic action (see Poor Balance), but unless you fail this by 4 or more, you only drop down safely onto all your feet.

Ready-made costs: Mostly you'll use Extra Legs to build four-leggers. A pair of Extra Legs costs 3 points for non-kickers. With default kicking ability, a pair costs 8 points for extra back legs, 10 for extra horizontal rearers, 11 for extra semi-upright rearers, and 13 for extra upright rearers.

Other notes on rearing: If you make no distinction between your default legs and Extra Legs, give your default legs Horizontal Rearing for 2 points, Semi-Upright Rearing for 3, or Upright Rearing for 5. Of course, you'll have to walk on some Extra Legs to do so! This is appropriate for a radial-shaped creature with no "front" or "back"; any legs can be raised up equally.

For any creature facing the roll to avoid falling from Lame or from raising itself up on back legs, allow a P/E Balancing skill to replace DX in the roll (see Book 4). Use all the same modifiers. The skill is appropriate for a dog or other animal that learns the trick of walking about on hind legs particularly well.

Legless creatures have a certain amount of body length that stays on the ground (see Posture), but can usually raise another half of that length into the air, with penalties similar to Horizontal Rearing by default. Pay 1 point for penalties similar to Semi-upright Rearing, and 2 for Upright Rearing. Take a -1 point disadvantage if you can't rear up at all.

Blobs: The Amorphous Body trait looks at Limb Extrusion, the ability to create limbs as needed.

Number of Legs options: no legs (Sessile; Quadriplegic; Single Leg or other legless movement); Lame (Crippled Leg; One Leg; Paraplegic; Quadriplegic); Single Leg; default two legs; Extra Legs; Limb Extrusion.

Leg Design

Modified Leg ST

Assume leg ST covers whole "lower-body" ST, affecting load-hauling and carrying ability (used to compute encumbrance), jumps, kicking damage, etc.

You can adjust it by setting ST appropriate for the legs and then buying arm, jaw, wing, and other ST areas up or down. Or start with a ST stat for all of those, and adjust only leg ST: use a -50% limitation (Legs Only) on the cost of modified Combat and Load ST.

In uncertain cases (wrestling, climbing, etc.), assume extra leg ST offers no bonus, or let it offer a small bonus. Strong Grip below offers a guideline for such a bonus.

Leg length

By default, leg length is around half linear dimension; minor variations don't matter. But for really different lengths, try the below. The base cost of the below adds to the cost of the legs' striking ability; there may be other costs for modified mobility.

Long and Short Legs will affect height, but overall Size doesn't change (for purposes of arm Reach, cost of Size, etc.), just the length of your legs.

Long Legs (new)

2.5 points/level per pair

You have unusually long legs. Each level increases leg length and Reach by one Size level, and costs 2.5 points per pair.

Add Enhanced Move and Enhanced Jump as you like. (Suggestion: one level of each for every two levels of Long Legs.) But Poor Balance is also an appropriate addition.

Short Legs (new)


You have unusually short legs. Point value depends on effects:

Other effects: Your low center of gravity may make you stable as a rock – but then again, watch penguins run. A level or two of Improved Balance is optional.

Add Reduced Dodge to any of the above if you like.

Mixed leg length: A creature with two legs of different length would likely be Lame. Creatures with more than two legs can have front and back legs of differing length, if the body is sloped oddly (a Brachiosaurus comes close) or the longer legs are folded effectively (a frog or grasshopper).

In general, buy running Move appropriate for the shorter legs, and jumping distances appropriate for the rear legs. Use Reduced Move (land), Enhanced Jump, or both; frogs walk slowly but hop beautifully.


Multi-legged creatures are usually restricted to very low kicks to the front, unless they rear up on the back legs first. Rear legs may have trouble kicking into front hexes, and vice versa; that's a special effect of body layout. Try Extra Flexibility to solve that problem.

Many animals do manage pretty good kicks to the rear with those back legs. As a free option, reverse "front" and "back" for any set of kickers – a mule's back legs can kick well to their rear but poorly to their front.

Another modification:

Poor Kicker (new)

-1 point/level

Your legs don't kick effectively. Each level subtracts 20% from Combat ST for kicking damage, and gives -1 TH (or -2 for targets higher than the waist).

At 5 levels the Rule of -5 gives you No Kick for -5 points. This is appropriate if you have no legs!

Advanced rule: Instead of the above flat cost, reduce the value of all default legs' and Extra Legs' striking ability by -20% per level of Poor Kicker. With No Kick, for example, Long Legs has no cost – long legs that can't kick offer no particular merit.


Options for feet:

Large/Small Feet (new)

0 points/level

Each level adjusts the Size of your feet by 1 level. Large feet make good stomping weapons and may support you better on soft surfaces. Consider Improved Balance for your wide, stable base. On the down side, large feet are easier to hit in combat.

Small feet make for harder combat targets, but they're no good for stomping roaches, and the GM is free to have fun when you try to walk on sand, snow, or mud.

Those are 0-point effects. Add modified foot HP separately if you like, as appropriate for changes in size.

Hooves (new)

0 points

Let Hooves provide DR (2 x Linear Scale) to the feet. At the same time, they reduce Stealth by 2 or more, and may require metal shoes or other special care to avoid painful problems after long runs. Hooves are a 0-point effect.

Hooves often have the Small Feet trait. But if they're big and heavy, consider Blunt Claws instead.


Posture was discussed earlier as a special effect describing orientation of the upper torso. But how you orient your legs also has interesting effects:

Stance (new)

0 points

Stance refers to how you position your legs. It's what divides dinosaurs into two taxonomic groups, the "bird-hipped" Ornithischia and the "lizard-hipped" Saurischia.

Multiple stances: Any creature can adjust its stance, but with discomfort and miscellaneous penalties: a human in a crouch takes a Low Stance and moves slowly. If you can freely change your stance without Move penalty, pay 1 point for the ability to switch freely between two, or 2 points for all three.

Miscellaneous leg options

Silence is easily ascribed to soft padded feet. Bowlegged is a trivial form of Lame.

Leg Design options: Modified Leg ST; length (Short Legs; normal; Long Legs); Poor Kicker; Inaccessible Propulsion (land); Stance (High; Low; Very Low; multiple); feet (Large/Small Feer; Hooves) Silence; Bowlegged.

Other Land Mobility Traits


Enhanced Move is common in creatures with strong legs or an efficient running build. Rules of thumb used for building real creatures in Book 7: Add one level for a multi-legged design. Add one level for creatures that are really built for speed, two extra levels in extreme cases. (But you don't need more than two or three levels for even the fastest mammals; see the cheetah write-up.) Reduce a half level for stiff, straight legs (common in large herbivores that need to bear a heavy body).


Here's an expansion of a GURPS trait:

Sure Footing (type) (new)

5 points

You take no DX or other "bad footing" penalties for any one type of difficult terrain. Ice Skates from CI p. 58 are Sure Footing (ice); others types include snow, sand, rocky, and mud/swamp.


Any creature has a default jumping ability. See Book 4's jumping rules for everything on the topic.

If you like, jumping can be your normal mode of movement. This would be very tiring for most creatures (try hopping down the block), but not for some:

Jumper (new)

5 points

You can sustain a jumping movement at no energy cost over normal movement, and can hop continuously with no readying between jumps. (You can also use your broad jump distance as Retreat distance.) Kangaroos are a good example, storing energy between jumps in oversized elastic tendons.

Your normal Move becomes your broad jump distance, or running broad jump once you get going. Buy Enhanced Jump for more speed. Over the long run this can be cheaper than high-speed running, but there are disadvantages: you can't turn or stop in mid-jump, and you Dodge at -4 in midair (or cannot defend yourself at all if jumping with All-Out action).

You still keep your regular running ability (unless you buy it down through Reduced Move, which has no effect on your jumping ability).

Enhanced Jump (new)

5 points/level

Like Enhanced Move, each level adds 100% to base jumping distance. A half level adds 50% to distance and costs 3 points. Creatures achieve this trait through abnormally large leg muscles, mechanical designs better adapted to jumping, or improved elastic tendons to store energy between jumps.

Super Jump (revised)

10 points/level

This works as it does in GURPS, with each level doubling jumping distances. It's best suited to non-natural designs.

Non-muscle acceleration: If you use Book 4's detailed rules, tiny creatures will have a very poor jumping ability due to limitations in the speed of muscle contraction. That's why insect jumpers use non-muscle acceleration mechanisms, including "springs" made of elastic resilin. Let one level of Super Jump have the effect of removing this limitation on small creatures' jumping, instead of the usual doubling of distance. This lets them jump as well as much larger creatures.

Beyond that first level, Super Jump and Enhanced Jump have usual effects.

Poor Jumper (new)

-1 point/level

You are a naturally poor jumper. Reduce jumping distances by x2/3, x1/2, x1/3, and x1/5, for one to four levels.

At 5 levels the Rule of -5 kicks in: you have No Jump for -5 points.


If you're terrestrial, take a -4 on Running, Hiking, Climbing, Jumping, and any other land mobility skills for -1 point. Or for a max -5 points, take -4 on all of the above skills.

If you're non-terrestrial, a -1 point Incompetence gives you -4 on all land mobility skills: your Flopping, Crawling, and any others the GM allows you.

Other Land Mobility Traits options: running options (Reduced Move (land); Enhanced Move (land); Hyper Sprint (land); Super Running); Sure Footing (type); jumping options (Poor Jumper; Enhanced Jump; Super Jump).

Water Mobility

Water mobility traits resemble their land cousins, with some differences:

Number of Swimmers

For game purposes, any appendage used to swim is a "swimmer". Single Leg works well for the tails of fish and whales. Some swimmers are muscular aquatic "wings" that ripple through the water, as on a ray. Treat these as your default pair of legs in function, TH, HP, etc., if not in appearance.

Aquatic or amphibious creatures: By default, you use only your swimmers to get around, just as a land creature uses only its legs. If you do need to use your arms to swim, then you're in the same position as a terrestrial creature that needs to use its arms to walk! See the rules on arms below.

Terrestrial creatures: By default, you use all your limbs for your limited swimming ability. (It's the reverse, going from water to land: an aquatic creature needs all the limbs it has for its slow crawling.)

Single Swimmer

The aquatic version of Single Leg, this treats two default swimmers as one large one with HP equal to HP x2/3. Swimming with the tail portion of the body (carangiiform propulsion) is Single Leg [0]; swimming with the whole body (anguilliform propulsion) is Single Leg [0] and Inaccessible Propulsion (water) [5].

Extra Swimmers

Additional swimmers make it harder for an enemy to take you out of action. Ignore as a special effect if you like, or buy swimmers over the default two as Extra Swimmers, just like Extra Legs. The base cost is 1.5 points per Extra Swimmer, plus striking ability (which you may have already paid for if the swimmers double as land legs). Instead of balance bonuses, the extra fins act as stabilizers and rudders that confer Swimming bonuses. You might also gain a little extra power in aquatic Contests of pushing or pulling (see Book 5).

Number of Swimmers options: type of swimmers (existing arms, legs etc.; dedicated swimmers); number of swimmers (none; Single Swimmer; default two; Extra Swimmers).

Swimmer Design

Motive power

For detail, note what percentage of motive power each swimmer provides and how much Move suffers if it's crippled. Swimmers also provide maneuverability: reduce Swimming skill by 1 for each 10% Move lost, Dodge by 1 for each 20% lost.

Example: Your fishlike tail provides 90% of your Move, and other fins the remainder. A shark chomps the tail off. You're a bleeding half-fish with 90% less Move, a -9 on Swimming, and a -4 on Dodge. Sorry, chum.

Inaccessible Propulsion (water) reduces your reliance on swimmers for mobility.

Advanced rule: For detail overkill, treat motive power (Move) and maneuverability (Swimming skill and Dodge) separately when dividing them among your swimmers. A dolphin might have all its thrust in its tail, but much of its maneuverability in its front flippers. Lose the tail, and thrust is gone; lose the front flippers, and maneuverability tanks.

Swimmer "feet"

The tip of a swimmer, whether hand-like, foot-like, a fin, a fluke, or an undifferentiated lump, can be targeted and damaged like a hand or foot. Loss reduces that swimmer's mobility to x1/3.

A swimmer's tip may be not be made smaller. You can make it bigger by spreading it out into a giant flat fin. Let each level of "Large Foot" give foes a +1 to target the fin, and include a level of Reduced Blowthrough for the fin, for a 0-point effect. Such large fins will also likely boost swiming thrust; the cost of this is in the cost of your final natural encumbrance.


Your swimmers' thrust is the same as your Load ST by default, but you can modify that as you like for number of swimmers, size of fins, disabilities, etc.

It would seem obvious to multiply thrust by the Area Scale of large or small fins. But it's harder to move a larger fin through water; the larger the fin, the lower the frequency of its beat. The net effects of fin size on thrust are uncertain. In the end, where to set thrust is your decision.


Default swimmers can "kick", often in the rear direction [0]. Poor Kicker is available. Striking ability for Extra Swimmers is an additional cost, as it is for Extra Legs. "Rearing up" will probably have no meaning underwater, so don't reduce cost.

Note that if your swimmers double as arms, legs, etc., you may have already paid for their striking ability. Of course, you can also have arms or strikers that don't double as swimmers.

Swimmer length

Swimmers' length matters if they can strike; the cost of Reach will be built into the cost of arms, strikers, or aquatic "legs" (use Long/Short Legs).

If length affects your mobility, add traits as appropriate.


If too much weight is getting you down, you can gain lift through the aquatic equivalent of airfoils. Borrow the rules from air movement below.

Swimmer Design options: thrust and stabilization; Inaccessible Propulsion (water); striking ability (No Kick; Poor Kicker; normal; other); length (Short Swimmers; normal; Long Swimmers).

Other Water Mobility Options


Lame isn't appropriate underwater, as balance and jumping modifications don't apply. Build aquatic Lame with Reduced Move (water), Reduced Dodge (water only), and possibly an Incompetence for aquatic skills. Reduced thrust is also very likely; the point value of that is that of the worsened natural encumbrance it brings.

Missing swimmers might also reduce Swimming skill, worth -1 point per -4 skill for aquatic creatures.

To mirror the land disadvantage, let up to -30 points of the above pile up into one Lame disadvantage. This is for use with the Overlapping Disadvantages rule.

Stance and balance

Jumping-related traits and Stance have no meaning underwater.

Improved Balance might help a fish regain control after knockback or turbulence, but generally won't be of much use.

Sure-Footed won't be of use either, though you could imagine "Sure Swimming" equivalents that help swim through underwater turbulence or aid swimming on a choppy surface. Let these halve any Move or skill penalties.


Default buoyancy for a creature is the same as that of water, letting you float on a level with neutral buoyancy. This is completely independent of size and weight; a blue whale is as buoyant as a minnow. You move upward or downward by swimming in that direction. You can be more or less dense, though, making use of fat or a gas store to float, or heavy bones to sink. You can even adjust your density on the go – fish accomplish this through swim bladders.

Positive and negative buoyancy are mentioned earlier; buy the appropriate level of fixed or adjustable buoyancy.


Many aquatic creatures spend their time on the sea or lake bed. This is easy to build: use negative buoyancy for bottom-dwelling fish that lie around peacefully, swimming only when they want.

Aquatic creatures may be able to walk on the sea bed using their land mobility, if any. Switch to normal land encumbrance rules when walking underwater. However, it should be slow; without any complicated rules, cut your running Move by half or more.

The above might be the case for an octopus or lobster, while many crabs will have full-blown Amphibious for decent walking ability on sea bed or beach. But walking ability alone may not be enough for you to get about on land – you'll need to breathe air and have the strength to haul your weight. King crabs and octopi can only drag themselves weakly on land.


If you're aquatic, take a -4 on Swimming, Diving, Speed Swimming, or any other water mobility skill for -1 point, or -4 on all such skills for a max -5 points.

If you're not aquatic, take a -4 to all water performance skills for -1 point. This is a fairly common human Incompetence, and is definitely worth a character point. Our planet is three-fourths covered by water, and no adventurer is likely to avoid a dunk forever. (Regardless of what CI says, allow this Incompetence in racial designs too.)

Other Water Mobility options: Lame (Reduced Move (water); Reduced Dodge (water only); Incompetence; reduced Swimming skill); Improved Balance; Sure Swimming; buoyancy (negative; neutral; positive; adjustable).

Air Mobility

Flying movement rules need to work a little differently from those for walking or swimming. The latter are "built in" and mundane, with default competence in one, and in the other a default poor ability that can be brought up to speed with Amphibious. But you have no default flight powers, and gaining them will cost you more than 10 points.

Zoologists speak of four types of flight: parachuting, gliding, powered flight, and soaring. To these we have to add wingless flight and lighter-than-air floating for fantastic designs.

The basics

You need an advantage to give you flying ability. Use Flight (CI p. 56) for a simple rule, or options below for detailed rules. Your base flying speed is twice base Move; boost with Enhanced Move (air) or Super Flight. Size should affect flying speed normally; multiply airborne Move by Linear Scale.

BS p. 139 offers special encumbrance rules for fliers, but GULLIVER uses the same rules for everything: multiply Move by the Move Modifier for encumbrance. However, Book 2's detailed rules let a little weight add a lot of encumbrance when in the air. Gravity's hard to resist.


You fall in air at a speed known as terminal velocity (tv). Call this a base 100 mph (Move 50) for humans. You can calculate a much more exact number using weight, area, and gravity (see Books 1 and 4).

Types of Flight


Also known as falling – but without the sudden stop.

Simple Rules: Use Catfall, and see Book 6 for the lowdown on falling. Happy landings.

Detailed rules: A large ratio of surface area to body weight slows terminal velocity, thanks to increased drag, or lift. Scientists call this parachuting, but here we'll use a more generic name:

Slow Fall (new)

5 points + 1.5 points/level

You fall slowly. Each level reduces your terminal velocity (tv) as follows:




































Slow Fall works by effectively cutting your falling weight to, or boosting your downward-facing area by, the square of the above multiplier, i.e., x1/2500 weight or x2500 area for 10 levels of Slow Fall.

With a low enough tv, free-fall acceleration almost disappears; you'll hit tv almost immediately. At 15 levels, you effectively don't fall at all!

Slow Fall presumes some sort of wings or wing-like surface area; see "Wing Design" below. Treat movement as gliding, but at up to only x1/10 forward speed. Only minimal maneuvering is possible; use Flight (Parachuting), defaulting to Parachuting -2 or Flight (Gliding) -2.

Enhancement: Your Slow Fall requires no conscious body control; you can be knocked out and still waft safely to the ground. +20%.

Limitation: You can't turn off Slow Fall. You have little control over descent speed; you can increase it by only up to 50%, probably by adjusting your wing shape or assuming a "diving" pose. -10%.

Limitation: You have no forward movement or maneuverability whatsoever while falling. -20%.

Catfall is a completely separate ability that lets you absorb the shock of impact. It may include a parachuting effect (seen in cats' spread-legged falling pose) to slow falls, but not enough to merit Slow Fall.


Gliding takes Slow Fall and adds the ability to move forward while falling. Gravity provides the momentum; you have no flight thrust. (Flying fish "flap" as they glide, but as far as researchers can tell this produces no thrust.)

Climbing and leaping adaptations are common in gliders. "Wings" themselves are varied: skin flaps stretched between limbs, extra-large feet, even elongated ribs that spread wide.

Changes from GURPS: Enhanced and Reduced Move affect forward speed, not rate of descent. Encumbrance does just the opposite: weight determines how quickly you descend. Maneuverability will generally be more limited than that of true fliers.

Simple rules: Use Flight with the Gliding limitation. For your rate of descent, find encumbrance and Move Modifier from WSR alone (including x5 multiplier for air), and divide the descent speed of 1 yard/second by this Move Modifier.

In a silly campaign, friends with lots of string can fly you like a kite.

Detailed rules: The rules below replace the Gliding and Controlled Gliding limitations:

Gliding (new)

5 points + Slow Fall

You fall slowly and move forward at the same time, maneuvering with the Flight (Gliding) skill.

Fanstasy gliders might gain Slow Fall from magic, gas bags, etc. However, realistic gliders rely on a high surface area-to-mass ratio (partially from shape, partially just from being small), or lift generated by airfoils.

For the latter, add the Requires Forward Move limitation [-20%]. Slow Fall drops as you slow down, per the airfoils rule, with all gliding ability lost if you slow to under one-third gliding Move. (A dive and pull-out may let you get restarted, if there's time...)

Example: The typical GURPS glider has Gliding [5] and 10 levels of Slow Fall [5 + 15], for a total of 25 points – but adds Requires Forward Move [-20% = 20] for airfoils. A humanlike version will fall at about 1 yard per second while moving forward, but will quickly begin falling faster if he slows forward movement.

Enhancement: Your gliding requires no conscious body control; you can be knocked out and glide in a straight line to the ground (or whatever gets in your way first; you don't maneuver). +20%.

Limitation: You cannot maneuver at all while gliding. -20%.

Gliding and weight: Your power doesn't affect your gliding Move, as it's unpowered movement! Natural encumbrance doesn't affect your forward speed at all. Weight will affect your speed of descent, though, using rules for tv.

Enhancements: Enhanced Move (air) and Reduced Move (air) affect forward Move normally, but not descent speed. Note that 5 levels of Reduced Move (air) will reduce Gliding cost by 5 points (for creatures that aren't truly aerial) and cut forward speed to x1/10 – in other words, it turns Gliding into Parachuting.


The following advantage reworks and replaces the Controlled Gliding limitation on Flight:

Soaring (revised)

5 points

You efficiently use warm-air "thermals" and other air currents to gain or maintain altitude with no significant effort. You can locate such currents on an IQ roll, or with a Soaring skill (M/E, possibly defaulting to Meteorology at -2). See Book 4 for more on soaring.

Any flier can buy soaring, though a parachuter will have a hard time maneuvering into (or out of!) a thermal.

Limitation: You can't turn off Soaring. Thermals will always carry you whether you like it or not; you may have to dive, or find a way out of the thermal, to fight the lift. -20%.

Soarers can ride thermals for hours, or glide with the contours of waves and hills. Soaring is found in birds, especially larger ones like albatrosses and vultures for whom continual flapping would be tiring.

Powered Flight

Wing-powered flight is found in mammals, birds, insects, and possibly prehistoric reptiles.

Simple rules: Use Flight with the Winged Flight limitation.

There's also a Small Wings limitation that's a -10% limitation. The wings only help steer and you don't need big wingspan, as described in CI. Wing injuries reduce Flight skill and Dodge, but not flight thrust.

Detailed Rules: Use a Powered Flight trait:

Powered Flight (revised)

30 points

You fly through the application of thrust. For a natural creature, this requires wings.

You may add Slow Fall or Gliding for half cost. Typical insects or hummingbirds pay [30] (no extras; their wings don't stop beating); typical birds add the standard 20-point, airfoil-based Gliding purchase above [30 + half of 20 = 40].

By default you can hover or move backward at half speed; take a -15% limitation if you cannot hover, -20% if you cannot hover or move backward.

Powered flight and gliding: GURPS doesn't say whether powered flight includes the ability to glide as well. Built-in gliding doesn't need to be the default condition for flight – it isn't in insects, and they far outnumber birds! Given the small cost difference between GURPS' Gliding and the far more useful Winged Flight, GULLIVER rules that the ability to glide (or just fall slowly) while not flapping is a separate ability. It's half price, though, as the utility of gliding is greatly reduced if you can already fly under power.

Weight and flight: You'll definitely want to design a powered flier with a good enough WSR to stay aloft and actually move somewhere. But even if you are too heavy to fly, Powered Flight allows some maneuverability in air, and lets you slow your falls through wild flapping. See Book 4. It's not much benefit for the cost, but it makes for an amusing character.

Wingless flight

This is powered or unpowered flight that works without wings. Super powers, magic, or jets are the explanation. No Earth creature flies this way – biological jets are inefficient propulsion even for swimmers, impossible for fliers.

Wingless powered flight includes a free ability to "fly" through water at half flying speed – though if you're not aquatic or amphibious, you'll suffer the usual skill penalties and risks of drowning.

Simple rules: Use GURPS' Flight advantage as is. Think of it as Winged Flight with Inaccessible Propulsion (air).

Detailed rules: Buy any of GULLIVER's above flight abilities and add Inaccessible Propulsion (air) for 10 points.

As in the above rule for powered flight and gliding, wingless flight means you have your jets in gear at all times. Add Gliding to take it easy once in a while.


If you're so light you float, you'll have more thrust to divert to forward movement.

Simple rules: Don't worry about weight and encumbrance effects; just add some Enhanced Move (air) to simulate the assistance of floating.

Detailed rules: Static lift reduces your weight, resulting in Slow Fall and improved encumbrance (possibly in more than one Environment). Purchase normally.

Static Lift below refers to lift great enough to reduce weight by 100% or more. You're as light as or lighter than air. This can come from magic, or a very low density – about one-eight-hundredth that needed to float in water!

If you have neutral buoyancy in air, you'll float on a more-or-less even keel. But without some sort of thrust, you'll have little mobility. Add Powered Flight to get somewhere.

Static Lift (new)


Static Lift reduces weight to zero or less.

If zero, buy the maximum level of Slow Fall (no fall!) and pay for the natural encumbrance you have with no weight.

If weight is negative, choose your negative weight in pounds. Pay for Slow Fall (no fall) and your natural encumbrance. Now pay 10 points to start floating upward, at a terminal velocity based on your negative weight. You can choose to rise more slowly than that, but normally not more quickly – if you can, you have Powered Flight. You have very limited maneuverability and forward movement while rising, per Slow Fall.

Limitation: You can't adjust Static Lift speed, and only rise at your maximum speed. -10%.

Limitation: You have no forward movement or maneuverability whatsoever while rising. -20%.

Also see rules for gas bags under "Density". This is a limitation on Slow Fall, Static Lift, or any traits that result from the bag.

Types of Flight options: parachuting (Slow Fall); gliding (Gliding; Slow Fall); soaring (flight traits; Soaring); powered flight (Powered Flight; Slow Fall); wingless flight (flight traits; Inaccessible Propulsion (air)); floating (Slow Fall; Static Lift).

Wing Design

The below apply to either gliding or powered wings.

Number of wings

Wings normally come in pairs, with at least one wing on each side of your body. An odd number of wings or a large Single Wing (the equivalent of Single Leg) may work if you can explain how! (A Single Wing as a parachute is reasonable.)

Extra Wings: Multiple wings make it harder for an enemy to ground you. Buy Extra Wings like Extra Legs, at 1.5 points each. The cost looks expensive, as a cheap upgrade to wingless flight would remove all the burden of wings! But let Extra Wings act as stabilizers and aerilons, conferring Flight skill bonuses equal to the balance bonuses from Extra Legs.

Motive power

Unlike legs or swimmers, loss of all wings on one side of your body will remove all flight ability; base your mobility on the side with the greater damage. For example, the loss of three left wings on a creature with six wings per side will cut mobility by 50%, whether the other side also has three crippled wings or no injuries.

Suffer -1 Flight skill for each 10% loss in mobility, -1 aerial Dodge for each 20% loss.

Inaccessible Propulsion (air) reduces your reliance on wings for mobility.

Advanced rule: If you like, borrow the notes from Swimmer Design and assign a degree of motive power and maneuverability to each wing – but the total for any one side should be 100%. Or maneuverability can be elsewhere: a bird, for example, might have 100% of its thrust in its wings, but only 60% of maneuverability in the wings, 40% in the tail.

Modified Wing ST

Flight thrust has no effect other than on air mobility. Raise or lower thrust to any arbitrary level; the only cost is that of your airborne natural encumbrance.

For realistic designs, flight thrust of Load ST x1.5 or so works; Load ST x2 is a reasonable limit for designs with mighty wing muscles. However, hoverers like hummingbirds may go even higher.

If your wings are also arms or strikers, their Combat ST and Load ST are separate from flight thrust. Buy modified ST for arms/strikers as you would normally, using the 50% cost from Modified Arm ST. That'll also affect your wings' load rating:

Load rating: Your whole weight is suspended from your wings in flight, and like any limbs, those wings can only bear so much. Let "load rating" equal Load ST. This is again separate from flight thrust, or any treatment of weight for maneuverability purposes.

Make a quick check of your WSR, based on the wings' Load ST, to see how burdened they are. Normally you'll be fine. At Super-Heavy encumbrance you're approaching the limits of your load rating: you maintain whatever mobility (if any) you have with that amount of weight, but your wings are straining to stay extended. You're tiring rapidly. At Extreme encumbrance your wings fold up or otherwise collapse!

Airfoils lift your wings, but your body's full weight still hangs from those; there's no lessening of the load on your wings. Lift from a buoyant body, however, does reduce your load.

Even if you don't have wings, the GM can use a load rating to set some weight limit on your high-tech or magical power.

Integrated arms and wings

By default, wings can not strike or manipulate (think of an insect's wings). But they can be part of your arms, strikers or other appendages. These can be default appendages, or extra ones bought normally.

You cannot fly if the integrated appendages are crippled or hampered. This includes holding large objects in arms. Using the appendages to strike in midair combat requires a Flight roll to maintain control.

Integrating appendages and wings isn't limiting enough to merit the Nuisance Effect of no arms/strikers. You can make quick midair punches or knife stabs, as long as you can handle the Flight rolls afterward. You can hold small objects in your hands just fine while flying.

See rules below on the cost of combined arms/wings.

Wing size and area

Default wings are big: each is about as long as you are, with impressive surface area. Call a wing -2 TH, like an arm, but -0 TH if it presents a front-on, extended spread. Your wingspan is twice wing length; you need that much room in order to take off or maneuver.

You can have Large Wings and Small Wings, just like Long and Short legs. These refer to the size of your wings relative to the rest of you.

Area: This is only interesting if you're playing around with target sizes, terminal velocities, etc. Assume default wings each add 150% or so to your area in the "falling" direction. For two default wings, that's +300% area and +1 (almost +2) to your Size as a front-on target with wings spread wide. That area roughly halves descent speed using terminal velocity rules. Even if you can't glide, you'll fall more slowly with wings extended.

In the direction of flight, assume your default wings' leading edges add only 25% or so each to the area you present. That will increase drag, though it doesn't make for a significantly larger shotgun target.

See the Appendix of Book 1 for more detail.

Large Wings: A bigger wingspan means a bigger target, and you'll need more space to maneuver. Each level of Large Wings adds 1 to your wings' Size as targets, with appropriate changes in wing span and wing area.

The benefit is a slower descent rate parachuting or gliding. You can also play at enveloping foes in your big wings like a cloak, though you might want to land first. Large Wings are a 0-point effect, but any Extra Reach for strikers or manipulators built into the wings must be bought normally.

Soaring and effective airfoils all go well with Large Wings. Drag will tend to be high, slowing your speed. (Long, narrow wings like an albatross's can cut the extra drag somewhat.) Effects on flight thrust are uncertain, combining larger area with the difficulty of flapping long wings. But airfoil effects make Large Wings a good choice for fliers like pelicans, eagles, or anything larger.

Small Wings: Realistic Small Wings are just like normal ones, only small. Each level of Small Wings subtracts 1 from the wings' Size, with appropriate effects on wingspan, wing area, descent speed, drag, etc. This is a 0-point effect. Buy short Reach for any attached strikers or arms normally.

Small Wings may suffer from little or no airfoil effect. Soaring is unlikely. Effects on flight thrust are uncertain, combining smaller area with a higher rate of beating. Small Wings are a good choice for small creatures, who don't need airfoil lift but can use any cut in drag. Short, weak wings coupled with static lift also let you build a cute, slow-flying bio-blimp.

Another type of Small Wings comes from GURPS' -10% Small Wings limitation: the wings aren't really needed to keep you aloft. To get this effect, forget the limitation and build Small Wings as above, adding the 5-point version of Inaccessible Propulsion (air): wing loss has only half normal effect. Or tweak this so wing loss has full effect on maneuverability and no effect on thrust – that matches the GURPS write-up.

Fixed wings

Your wings are straight out and unmoving like an airplane's! You gain thrust from jets, magic, gravity (gliding), or other propulsion, while the wings carry maneuverability and possibly airfoil functions. Treat this as wingless flight, but with the 5-point version of Inaccessible Propulsion (air). Take an additional disadvantage for the nuisance of appendages sticking permanently outward: -1 point if small, -2 if default size, and an additional -1 per level of Large Wings.


Rapidly-beating wings, like those of insects or hummingbirds, create their own interesting aerial lift effects, but for design purposes a good flight thrust models these fine. Airfoils here are wing structures that creates lift through forward movement through the air. The lift lets you divert less thrust to staying aloft, and more toward speed and maneuverability.

Simple rules: Don't worry about such stuff. Just build a design that can fly, and take the -20% Cannot Hover/Fly Backward limitation on your Powered Flight or Gliding. You can't hover, move backward, or fly at less than half your full Move.

Detailed rules: First, check your encumbrance normally and pay whatever that's worth. You might even be too heavy to fly at all, in which case you merit the -20% Cannot Hover/Fly Backward limitation on your Powered Flight.

Now determine some amount of lift that airfoils provide – lift equal to 80% or so of body weight is good. Figure new encumbrance and Move in the usual way, from total weight minus this lift.

Pay the cost difference for those extra, improved levels of encumbrance, but with a -20% limitation (Requires Forward Move). The details of that limitation: If you slow to between x2/3 and x9/10 your top speed, you lose half those extra levels of improved encumbrance. If you slow to between x1/3 and x2/3 top speed, you lose three-fourths of those levels. Any slower than that, and the improved encumbrance is lost.

Adding weight: Carried weight increases encumbrance, which lowers speed, which further increases encumbrance, which... Unless you want to tackle computation of the complex equilibrium, use this shortcut:

Increase encumbrance normally if you take on weight, then increase it again by half as many levels (round down).

Advanced rules: What's a correct amount of lift from airfoils? A flier that can glide has Slow Fall that reduces falling speed by some amount (such as x1/50). This happens because weight after lift is reduced – by the square of Slow Fall's effects, to be exact.

Example: A 100-lb. glider with Slow Fall x1/10 has weight reduced to x1/10 squared, or x1/100 – airfoils provide 99 lbs. of lift! If Slow Fall were x1/50, air foils would be providing over 99 lbs. – effectivly 100 lbs. – of lift.

But lift depends on velocity and wing area. With no data on hand regarding the lift of a bird wing per unit of area at a given air velocity, here's an educated guess that's probably generous in its lift, and may not even be correct within a degree of magnitude, but is something to play with:

Maximum lift in pounds = (Move in yards, squared)/10 x Area Scale of wings x number of wings

That's for default wings, using Area Scale x1 for default wings and appropriately adjusted Area Scale for small or large wings. With wings of mixed sizes, compute lift for pairs separately, and combine.

With the above you can play games such as finding your maximum speed at gliding weight, and seeing if lift at that speed is actually enough to get you that weight.

Example: Your 120 lb. winged human design has gliding Move 15, and you've decided on Slow Fall x1/50, which means lift while gliding is almost 120 lbs. (120 - 120/2500 = 119.952, to be unnecessarily exact). Will default wings actually provide that much lift?

At Move 15, best possible lift is 225 / 10 x 1 for Area Scale of wings x 2 wings = 45 lbs. Sorry, that doesn't reduce weight much. Try a level of Large Wings, giving the wings Area Scale x2. Lift becomes 90; still not to get the zero weight we're assuming here.

Two levels of Large Wings do the trick, confering enough airfoil effect to generate well over 120 lbs. at Move 15. Ignore the extra amount; lift for these wings is what Slow Fall indicates.

Alternately, gliders can start with wing size and Move, and see what lift and descent rate are indicated:

Example: Your 120 lb. winged human design has gliding Move is 15 and Large Wings x1. As above, this provides only 90 lbs. of lift, so weight gliding is 30 lbs. That's 30/120 = 0.25 times your normal weight, implying Slow Fall equal to the square root of that, or 0.5. You purchase Slow Fall x1/2 (two levels), halving your falling speed when gliding. (That's a pretty precarious rate of descent; why not go for the bigger wings?)

All that is for airfoils when gliding, whether you're a full-time glider or a powered flier coasting for a while. Airfoils during powered flight work similarly, with one difference: airfoils generate less lift while the wings are flapping. Figure lift as above, but cut it by some amount – by 80% for the sake of putting some rule in place, until actual data suggests a better number.

Of course, powered Move won't likely be the same as gliding Move. You need to find powered Move after first finding encumbrance . . . but to find encumbrance where lift is involved, you need to first know powered Move.

Example: Your 120 lb. winged human has Slow Fall x1/50 gliding at Move 15, indicating (as above) Large Wings x2 and nearly 120 lbs. of lift at Move 15. Assume only 80% as much lift from airfoils, or 96 lbs. of lift and 24 lbs. of weight, during powered flight.

Assume thrust 10. WSR = 2.4, x 5 for air = 12. MSR is 12. Effective MSR = 12 x 1.6 = 19.2 = Neg 2 encumbrance and Move Modifier x1.2. Powered Move is (let's say) Basic Speed 5 x 1.2 for enc x 2 for flight = 12

All fascinating, if you've really got the time and inclination. Further poking around into this topic is left to the brave.

Wing position

Wings are protected normally by your DR; see Retraction if they're not. The position of wings when not flying can be either extended (like a butterfly or dragonfly) or held against the body (like a beetle or bird). This is a special effect; the latter makes it harder to individually target wings when you're not flying, but damage to the appropriate part of the body (side, back, etc.) will have a good chance of hitting and injuring the stowed wings.

Strict GMs might charge a point for a creature that can freely choose either resting position.


Give wings half the "blowthrough" level of ordinary limbs; arrows and bullets pass through easily. The Modified Blowthrough trait can reduce this even more.

Cutting and crushing attacks, flame, shotguns, etc. will wreak full havoc on wings. Bullets or arrows aimed at the wing's structural struts (call these bones or stiffened tissue an additional -2 TH) will also hit solid stuff; ignore the halved blowthrough level. A lack of this weakness might be called No Struts, worth 2 points.

Wing Design options: none; Inaccessible Propulsion (air); power (modified flight thrust; modified wing ST); number of wings (Single Wing; two; Extra Wings); integrated appendages and wings; size (Small Wings; normal; Large Wings); Fixed Wings; airfoils; wing position; No Struts.

Other Air Mobility Options


Forget Lame for aerial use; balance and jumping modifications don't apply. Build wing disabilities or other flight problems with Reduced Move (air) and Reduced Dodge (air only), and possibly an Incompetence for flight skills. Further reductions in Flight skill might be worth -1 point per -4 skill for aerial creatures.

As with aquatic creatures, let up to -30 points of the above pile up into one Lame disadvantage, for use with the Overlapping Disadvantages rule. Of course, the worst you can do is the complete removal of flight abilities and their point cost (or up to only -80% of their cost if any ability remains).

Stance and balance

Posture and stance have no particular meaning in the air. Balance isn't a big issue while on the wing, but Improved Balance with the "internal" enhancement would help you recover from loss of aerial control. Sure Footing is meaningless in air, though you could invent a Sure Flying counterpart that halves Move and skill penalties caused by turbulent air.

Useful add-ons

If you want to be a high flier like the mallard duck (looking good at 20,000 feet) or the bar-headed goose (spied crossing the Himalayas at 29,000 feet), Pressure Support for high altitudes and Temperature Tolerance are musts. Keeping up with migratory fowl like the arctic tern (20,000 miles per year round trip) or even the lowly barn swallow (6000 miles per year) requires good gliding or soaring ability and Extra Fatigue.


Two unnatural traits you can add to existing flight ability:

Full 3D Flight (new)

10 points

You have unusual flight maneuverability: instead of climbing slowly, you can fly straight up at any time! If you have airfoils, they mysteriously work even when flying upward (assuming you maintain the required speed). This advantage includes the 5 point base cost of Slow Fall, letting you descend straight down while flying or gliding.

Position-Free Flight (new)

2 or 5 points

Normal fliers will have a set flight position (or one for forward flight and another for hovering, etc.). But not a showboat like you: for 2 points, you can fly vertically or horizontally without changing position – even "standing" – with no ill effect on speed, airfoils, gliding, etc. For 5 points, you can fly without penalty in a sitting pose, upside down, or reclining with a book! This is best suited to wingless flight.


If you're a true aerial creature, take a -4 on any air mobility skill for -1 point. Or for -5 points, you're just plain clumsy on the wing: take a -4 on all such skills.

If you're not a true aerial creature (which means all Earth fliers), take a -4 on all such skills for -1 point.

Other Air Mobility options: Lame (Reduced Move (air); Reduced Dodge (air only); Incompetence; reduced Flight skill); No Backward Movement; Improved Balance; Sure Flying; exotic traits (Full 3D Flight; Position-Free Flight); useful add-ons (Pressure Support; Temperature Tolerance; Extra Fatigue).

Space Mobility

The ability to accelerate in space is definitely cinematic. It's tempting to call space movement a fourth Environment, but it's really just flying – if you can fly in space, you can (theoretically) fly in an atmosphere.

Of course, as a living environment, space is something unique. Be sure to consider Vacuum Support before jumping out of the airlock.

Simple Rules

For great cinematic fun, just tack a +20% Space Flight enhancement onto your Flight, and take what you need from Vacuum Support to stay alive. You can now fly through space exactly as you do in air, using the same Move and maneuverability. See Book 4 for more performance details.

This is pure space opera silliness, in the style of Star Wars dog fights. Don't worry; in space, nobody can hear your physics professor scream.

Detailed Rules

More realistically, you don't have a maximum Move in space; you have acceleration. You can have any Move you want, given enough time to accelerate.


Start with Powered Flight, and add the Space Acceleration enhancement from Bio-Tech p. 136. If you like, multiply this purchased acceleration by your flight thrust x15 (max: Load ST x15) and divide by mass. That adds some no-cost individual variety to acceleration.

Further acceleration comes from Super Flight: double acceleration per level. Linear Scale, Enhanced Move, and Reduced Move have no effect.

You have only this acceleration in space, and no top speed. You decelerate only as fast as you accelerate.


Take a level of encumbrance appropriate to your acceleration. Suggestion: Start with MSR 50, divide this by your acceleration, and look that up on the MSR column of Book 2's Encumbrance Table.

For example, if you have 0.2 g acceleration, look up MSR 250 on the table: the equivalent of Extra-Heavy encumbrance. Ignore Move Modifier (you don't have a top speed); just use the modifiers for Dodge, Acrobatics, etc.


Revert to your aerial flight capabilities in atmosphere. Compute Move and encumbrance normally. You can have very slow space acceleration yet still have good acceleration and Move in atmosphere. Or you can be lousy in both: buy a poor space acceleration, and take poor flight thrust and high encumbrance, Reduced Move, etc. in atmosphere. Or you can fly well in space, yet be just plain too heavy to fly over a planet.

If you theoretically could fly in atmosphere given your weight and ST, but for some reason can't (your magical flight shorts out in gravity wells), take a -50% limitation on Powered Flight (but pay normally for the Space Acceleration enhancements). You can fly in space only.

Natural encumbrance

If natural encumbrance differs in atmosphere and in space, pay for whichever is more important to the GM's campaign. Ignore the extra cost of the other – or optionally, take one-fifth the cost difference of the other, as an advantage or disadvantage.

Space Movement options: none; Powered Flight with Space Acceleration enhancement; Super Flight.

Miscellaneous Means of Movement


Climbing is a form of land movement. Claws will assist climbing, as will manipulators, extra limbs, plenty of DX, flexibility-related traits, high ST, and low weight. Climbing skill is vital too. Book 4 ties these all together into climbing performance.

Enhanced Move (climbing) (new)

3 points/level

Enhanced Move (climbing) replaces the Super Climbing advantage. For normal climbing, each level acts as Enhanced Move.

If you're using Clinging, however, you're already a very fast climber; double the cost for your Enhanced Move (climbing). Either way, maximum climbing Move cannot be higher than ground Move.

Limitation: Your Enhanced Move (climbing) only applies when brachiating. Maximum climbing Move can exceed ground Move. -33%

Poor Climber (new)

-1 point/level

Your body isn't built for climbing. Each level acts as a level of Reduced Move (climbing), and reduces skill by 2. This is in addition to any normal penalties for your encumbrance, etc. At five levels, the Rule of -5 sticks you with No Climbing, which means just what it says.

Cost is -1 point/level for terrestrial creatures. If your primary Environment isn't land, you get the whole No Climbing package for only -1 point.

Clinging (revised)

25 points

You "stick" to walls, moving at half your base ground Move. You take no Climbing penalties for difficult surfaces, even smooth glass – think of it as Sure Footing (vertical surfaces) for lots of points – and your skill defaults to DX or 16, whichever is higher!

Climbing penalties from encumbrance will limit how much you can carry and still cling. Injuries and other hazards can also lower skill to the point where you run a good risk of falling. If you want to cling even with a heavy load or under bad conditions, raise Climbing skill normally; additional skill levels include additional "stickiness".

Generally, you need to use all of your limbs to cling, as with any climbing. Make Climbing rolls to stay stuck if you try to cling with limbs crippled or occupied; each limb not used to cling gives a penalty of (-16/your number of limbs).

You can safely break a fall by latching onto a wall on the way down. Roll vs DX to touch the surface. If you succeed, roll vs Climbing skill at -6, with an additional -1 per 5 yards fallen. Success sticks you to the wall; failure means you still manage to reduce effective falling speed by 20 mph. (ST comes into play here through encumbrance's effects on Climbing skill; you don't need to make any rolls vs ST.)

Limitation: Your Clinging takes a -4 skill penalty on loose or sandy surfaces [-20%], or alternately, -8 on anything but a smooth, clean surface [-40%]. This may represent suction cups.

Limitation: The opposite of the above: your Clinging works on anything but a perfectly smooth surface, like glass. -20%. This may represent small claws or burrs.

Limitation: On wet surfaces, your Clinging suffers -4 skill [-10%], -8 [-15%] or doesn't work at all [-20%]. This may represent glue pads or sticky slime.


To swing from tree to tree with your forelimbs, make sure you have arms of at least default length, with hands that can grip. Try for a good WSR too. (A hint from monkeys: short little legs trim valuable pounds.) Consider some Enhanced Move (climbing) if you have Long Arms.

Humans are equipped with the basics, but the Brachiator advantage makes you really good at swinging. Ignore the part of the GURPS description about needing ST 12 to use only two limbs; as always, it's WSR, not raw ST, that matters. See Book 4 for performance notes.

Climbing options: normal; Enhanced Move (climbing); Poor Climber; Clinging; Brachiator.


The Tunneling advantage (CI p. 69) lets you make like a mole or worm, but at superheroic digging speeds. Multiply Move by Linear Scale. Reduced Move (tunneling) works normally, for -5 points per level. Tunneling speed should not be faster than your normal running speed, but that's unlikely to be an issue.

While encumbrance usually won't affect tunneling Move, ST relative to the area of the passage should help. For detail, multiply your speed by Load ST, then divide by (10 x your Area Scale).

Limitation: You have realistic tunneling capabilities. You use all the limbs and claws you've got to tunnel; buy Reduced Move if you make do with clawless hands or just a mouth. Compute speed as above, but halve it. Tunneling speed can never be greater than your ground speed – and for humanlike creatures, that'll be ground crawling speed! You cannot go through rock, unless the GM rules you have the strength and hardened claws for the task. Even hard earth will halve speed again. -60% (applies to the value of any Reduced Move too).

Limitation: Shallow Tunneling. You can only tunnel deep enough to cover yourself, maybe a little deeper (up to 3 hexes deep, appropriate for your size). As an optional special effect, you can dig backward instead of forward, using your hind legs like a toad. Shallow Tunneling is good if you don't want to travel through the earth, and just need a quick hole for protection or ambush! -40% (applies to the value of any Reduced Move too).

Tunneling options: normal; Tunneling; Reduced Move (tunneling); Super Tunneling.

Exotic Movement

Walk on Air and Walk on Liquid let you treat those mediums as land. Use all appropriate rules for land movement, including encumbrance. Sure Footing (waves) would be helpful for water walkers.

Walk on Liquid is real under certain conditions: a tiny size, minuscule weight, and water-repelling hydrophobic feet will let you treat the surface tension of water as solid ground. The GM should limit this to creatures 1" or smaller, with appropriately tiny weight.

Here's a limitation for Walk on Liquid, appropriate for somewhat larger creatures:

Limitation: Basilisk Running. You can only run on water if you have Negative 3 or better encumbrance (for a fleet gait), two or more levels of Large Feet, and a Move of at least (20 yards x your Linear Scale). -33%.

Exotic Movement options: none; Walk on Liquid; Walk on Air.


Below are GULLIVER rules to replace GURPS' limb design rules. As mentioned under Mobility earlier, these stop short of a technically-precise solution; see the Appendage Builder System in Book X instead for a complete, mix-n-match system for appendages of all kinds.

Arm or Leg?

Arm or leg? For simplicity, GURPS draws a clear distinction. If it manipulates, it's an arm; if you walk on it, it's a leg. If you use it for both, it's an arm. There's not much mixing-and-matching you can do, although Bio-Tech extends the system a bit into legs that manipulate, etc.

Arms needed for propulsion in primary Environment

Build the arm as an Extra Leg, but starting with the base cost of an arm (whether default or extra). Combined arms/legs use a cost multiplier of from x1/2 to x1, depending on the severity of the penalty of raising the limb off the ground. For combined arms/swimmers or arms/wings, though, use x1/2.

Reduce cost for number based on total number of limbs: your first six are full cost, next two 1/2 cost, next four 1/4, next eight 1/8, etc.

Arms needed for propulsion in other home Environment

You only get a -10% limitation on the cost of the limb calculated so far, or a -20% limitation on the cost of the added Propulsion that comes later (the cost of Amphibious, flight traits, etc.), whichever nets you fewer points.

Arms needed for propulsion in non-home Environment

No point break – by default, you need all your limbs for whatever poor mobility you can manage.

Fine Manipulators

Fine manipulators can do delicate work; crude manipulators can push things around but not grasp or wield them.

If your appendage neither walks nor manipulates, it's probably a striker, possibly a wing, maybe even a tail or antenna. (And if it's none of those, then hey, better have a doctor look at that.)

Number of Manipulators

You have a default two arms, with fine manipulators (hands or their equivalent) on the ends. What about creatures without these manipulators? Two ways to handle this:

Simple rules

One Fine Manipulator and No Fine Manipulators leave you with some sort of crude manipulators with which you can push or kick things; if you don't even have those, take No Manipulators. On the other hand(s), manipulators above the default two are bought with Extra Arms. All these traits are detailed in CI.

Detailed rules

An arm has two main default uses: manipulating and punching. A creature with No Fine Manipulators loses that first use, but still has two limbs useful for punching! (GURPS designs sometimes miss this.)

Cost: The default arm is similar to a one-hex striker, with manipulatory ability. A generic one-hex striker costs 10 points and does thrust damage – but an arm punches for only thrust-2 damage, so it's a weak striker. Halve cost for this "puncher".

With -30 points as the cost of No Fine Manipulators, the manipulatory ability of the first two arms appears to be worth 15 points each. No Arms becomes -40 points, as the two default arms are worth 20 points each (5 points for the puncher, 15 points for manipulation).

Having any crude manipulator at all – an arm, a striker, legs, whatever – is worth something. Let's call it 5 points for one or any number. The loss of that, and loss of ability to kick [-5], is the difference between No Arms and No Manipulators. So, a snakelike creature has No Manipulators [-50]; if it also had a striker or two able to bat things around, it'd just have No Arms [-40] and No Kick [-5].

Location: Note that a manipulator doesn't have to be put at the end of some sort of striker! You could tack it right onto the body, though many tasks will become clumsy. Putting a manipulator on the end of a striker lets it gain the striker's reach for free and lets the combo wield weapons – at the cost of both becoming useless if the striker is crippled. It's a 0-point design choice.

Manipulator Table






No Manipulators




no manipulating limbs at all!*

No Arms (new)




non-arm limbs only**

No Fine Manipulators, One Arm (new)




one puncher

No Fine Manipulators




two punchers

One Arm (no attack)




one manipulator

One Arm




one puncher, one manipulator

One Hand




two punchers, one manipulator

two arms (both no attack)




two manipulators

two arms (one no attack)




one puncher, two manipulators

two arms (default)




two punchers, two manipulators

* No Arms [-40], No Kick [-5] and no other manipulators whatsoever [-5]. You can push things around with your head and body only.
** You've got legs and maybe some other appendages to perform crude manipulation, and can kick by default (add No Kick [-5] if not).

One Fine Manipulator isn't on the table; it can be bought with the costs and effects of either One Arm or One Hand, depending on whether that second puncher is there or not.

ST Cost Reductions: GURPS offers a -40% cost reduction on the cost of ST for creatures with No Fine Manipulators. That's reasonable – but while GURPS designs often use the -30 point No Fine Manipulators to model armless creatures, GULLIVER suggests -40 points for having no arms at all.

That leads to the obvious: use the above disadvantages as Nuisance Limitations on the cost of ST. No Fine Manipulators is good for -30% off the cost of ST, NFM (one arm) nets -35%, No Arms -40%, and No Manipulators, -50%.

GURPS doesn't offer a similar ST cost reduction for One Arm or One Hand, but consistency suggests doing so.

Extra Arms: A base 10 points per arm over two is fine, but some creatures have lots of arms, and an octopoid PC gets pretty prohibitive. Try a revised cost:

Extra Arms (revised)

10 points each

You have three or more arms. These are useful as extra strikers and manipulators, and as "backups" for injured arms.

Basic cost: Extra Arms cost 10 points each for the first two, covering "puncher" ability [5] and manipulator ability [5].

Extra Arms that only strike can be bought with the Striker rules.

Reduced cost: The first two Extra Arms are bought at full cost. Multiply cost for the next two by x1/2, the next four by x1/4, the next eight by x1/8, the next eight by x1/16, the next eight by x1/32. . .

Include the cost of Long/Short Arms, modified grip or Manual DX, etc., when reducing cost for number. But pay full cost for the most expensive pair, halve the cost of the next most expensive pair, etc.

Limit on number: Arms add weight, and there's only so much room for attaching them. Keep arm number reasonable, or build them thin (with low ST and HP).

Bonuses: Extra Arms help you in close combat, aiding TH in grapples and boosting ST in wrestling maneuvers; see Book 5.

Number of Manipulators options: none (No Manipulators; No Arms; No Fine Manipulators (one arm); No Fine Manipulators); one (One Arm; One Hand); default two arms; Extra Arms.

Fine Manipulator Modifications


Hands (or their equivalent) can perform fine manipulation and can grip things. DX is important for the former, while both DX and ST cover gripping ability. Some grip modifications:

Bad Grip (revised)

-3 points/level (max 5 levels)

Your fine manipulators have a weak grip. Each level reduces their ST by 20%, affecting ability to strangle a foe, wrest away a gun, etc. Each level also reduces DX by 1 for any task requiring a firm grip: many uses of Acrobatics and Climbing, catching things, melee weapon use, etc.

At 5 levels, you have No Grip! Your fingers can push and prod, but cannot grip anything. You can perform some fine manipulation tasks normally (typing), others at a -5 or so penalty (lock picking, perhaps), and yet others not at all (acrobatics requiring a grip).

Bad Grip affects all your manipulators. For a more detailed cost based on the number of manipulators affected, treat each level as a -10% limitation on the cost of affected manipulators. (Remember, your default two manipulators cost you a free 15 points each, or 30 points total.)

Strong Grip (new)


You can buy extra ST for your fine manipulators only. Use an appropriately low cost for this ST. A suggestion: total the number of points spent on fine manipulators, halve that, and call that a percentage cost for additional ST. (Example: a human PC has "spent" 30 points on two default fine manipulators. Halve that to 15: you buy additional hand ST at 15% cost.)

Strong Grip's ST will be useful for crushing things (like necks), holding on to contested objects, etc. You'll also gain skill bonuses in some situations: say, rolls to hang onto a ledge, climb a wall, or catch a heavy item (but generally not combat skills). A suggestion: +1 on rolls for each multiple by which hand ST is improved, using the progression x1.5, x2, x3, x5, x7, x10... Multiplying hand ST by 1.5 or more, but by less than 2, gives you a +1, for example.

Manual DX

Manual DX aids delicate tasks. Slender beings are more likely to have extra Manual DX, but you don't need to automatically give small designs lots of Manual Dexterity and slap big designs with Reduced Manual Dexterity. If relative Size modifiers are applied to fine tasks (say, a human taking a -1 on DX when picking a Halfling-made lock), you'll get the same effect.

Reduced Manual DX (revised)

-3 points/level (max 5 levels)

Each level reduces DX by one for tasks involving fine motor coordination. At 5 levels, you have No Manual DX! This is not the same as No Fine Manipulators; you can pick things up, grasp a lever and pull, even clumsily turn a dial, but delicate tasks like typing or lock picking will be impossible, or will carry at least a -5 penalty. Even writing would be a challenge. Think of a lobster claw: it can certainly grasp and manipulate, but could it play a piano?

Reduced Manual DX affects all your manipulators. For a more detailed cost based on the number of manipulators affected, treat each level as a -10% limitation on the cost of manipulators. (Remember, your default two manipulators "cost" you a free 15 points each, or 30 points total.)

Note: No Manual DX combined with No Grip equals No Fine Manipulators, in both effect and cost.

Large/Small Hands (new)

0 points/level

Each level adjusts the Size of fine manipulators by 1 level. Large hands are easier targets and may be clumsy for delicate tasks, but can more effectively grasp larger objects (including a foe's neck; see Book 5). Small hands are harder targets and are good for fine tasks, but can't hold large objects – normal weapons and tools may be very clumsy for you.

Those are 0-point effects. Buy appropriate modified grip ST and modified hand HP separately if you like.

Fine Manipulator Modification options: DX; Bad Grip; No Grip; Strong Grip; Manual DX; Reduced Manual DX; Large/Small Hands; Missing Digit.

Other Arm Modifications

Disadvantages that affect default arms have a flat point value; those that affect Extra Arms should be bought as limitations. Remember the -80% limit on limitation values! An arm that's short, weak, and clumsy is still an advantage if it's a third arm.

No Physical Attack

Arms that cannot attack physically (other than to wield a firearm or similar ranged weapon, but not to strike) don't pay 5 points for a puncher. See the discussion on default arm cost above. Extra Arms will have similarly reduced cost.

Modified Arm ST and DX

Higher stats: See CI p. 61 rules on improving arm ST and DX. These note that modified ST shouldn't use Enhanced ST pricing, but ignore that. If the creature as a whole is using Enhanced ST costs, the arms should too.

If Combat ST and Load ST differ initially, maintain their proportion in new adjusted arm ST. That is, if Grunt the Giant (Combat ST 26, Load ST 52) bought +3 Combat ST for an arm, he should also buy +6 Load ST.

Lower stats: To decrease stats, consider manipulator and striker costs separately. Decrease manipulator ST using Bad Grip and Decreased Manual DX.

Decrease the cost of the striker portion of the arm by -10% for each -20% ST, and by -10% for each -1 athletic DX.

ST and DX reductions can combine to a maximum -100% cost of the arm's striker portion – which removes all striking ability. The arm gains No Physical Attack.


Assume an arm's throwing strength is the same as its striking strength. An arm that cannot strike for damage cannot throw with any appreciable speed or force.

Allow Throwing equivalent of Jumping enhancements, if the trait seems to make sense. A chimpanzee, for example, has fused wrists and cannot throw like a human; use Poor Thrower x2 [-2], halving distances.


Long Arms (revised)

5 points/level per arm

Long Arms cost 5 points per arm per extra Size level of length. For 10 points one arm can be twice as long. Both default arms and Extra Arms can be made long.

Each level adds +1 to attempts to grapple (if two or more arms are used; halve this bonus otherwise), up to +4, and 10% Combat ST with a swing, up to +40%.

Long Arms might work like a tightrope artist's pole: if you have a matching set of Long Arms, you can buy Improved Balance, up to one level per two levels of Long Arms.

Short Arms (revised)


One or more of your arms are shorter than normal:

Arms shorter than the above are worth no extra points.

Adjusting cost: A percentage limitation on either the striker or manipulator portion of an arm affects Long/Short Arms by half as much. A -80% reduction in manipulator cost from Bad Grip cuts allows a -40% limitation on Long/Short Arms. A -100% reduction on striker cost from No Physical Attack allows a -50% limitation on Long/Short Arms. A useless "arm" with no striker or manipulator ability pays nothing for length modifications.

Other Arm Modification options: length (Long Arms; Short Arms); No Physical Attack; Modified ST; Modified DX.

Generic Appendage Modifications

Appendage HP

Modified appendage HP fleshes out stout legs or spindly arms. Adjust body weight as you feel appropriate.

Modified Appendage HP (new)


Treat Modified Appendage HP as Extra/Reduced HP for purposes of determining appendage HP. Purchase at 40% normal cost.

Example: You have HP 9 and buy 3 Extra HP at 40% cost, giving you HP 12 for purposes of appendage HP. Your arms and legs will have HP 6, your hands HP 4, etc.

To modify individual appendages, divide that 40% cost appropriately, treating arms, legs, strikers, and wings as equals. For a creature with four appendages,additional HP that affect only one limb's HP have a neat 10% cost.

A suggested limit on modified appendage HP is +100% or -50% of default HP, with more extreme HP available to limbs with appropriately modified ST and length.

Other resistances

Non-vital Appendages (new)

5 or 10 points

Your appendages can be damaged normally, but the injuries have little or no effect on your entire system's well-being. An insect's fragile wings, for example, can be shredded or even ripped off without immediate danger to life.

For 5 points, appendage injuries have only half normal effect on overall HP. For 10 points, they have no effect on overall HP. Shock and pain are similarly reduced. (If only some appendages have this trait, adjust cost in the same manner as Modified Appendage HP.)

Inaccessible Propulsion remains a different animal, modifying appendage injuries' effect on mobility, not health.

Limitation: Appendage injuries have reduced effect on overall health as above, but you still feel them normally, suffering full pain and shock penalties. -20%.

See Injury Intolerances for an very different trait.

Retractable appendages

Retraction (new)


You can pull appendages into your body or shell for protection. Retraction or extension works like Crouching: you choose a given position at the start of your turn, which remains in effect until your next turn, at which time you can change it again.

A retracted and sealed appendage can be hit through the body! Use the standard penalty for appendage size, with an additional -4; failure by 1 is a body hit. (A roll vs Zoology, Xenobiology etc., may halve the TH penalty.) A successful hit attacks the body's DR first, then half the body's HP, then the appendage's DR and HP.

A partially retracted appendage is half as long – an exposed but harder target (-2 TH). Treat as Short Arms/Legs (or nearly-useless wings), and apply additional penalties as appropriate for clumsiness.

Limitation: You can retract the appendage but not seal it off. It can be attacked through the socket at -3 TH beyond normal target penalty; the line of attack must be capable of hitting the opening. Damage hits appendage DR, then the appendage (hands and feet if these "block" the socket). Additional damage passes into body, ignoring its DR. -25%.

Limitation: You can only retract the appendage half way. -50%.

Limitation: You cannot retract individual appendages, only all retractable appendages at once. -10% if you have two to five retractable appendages, -20% if you have six or more.

Enhancement: Your appendages retract fast, allowing +1 AD vs attacks against them! +2 points per appendage (or pair for little things like antennae).


Curling up into a defensive ball helps protect vitals and the face (say, an additional -2 on foes' TH, or only -1 if protected by short limbs). But pillbugs and the like can really batten down the hatches.

Treat Curling as a special form of Retraction, at a base 1 point per affected appendage (including head) and 4 points for the vitals. Now add the "retract all equally" limitation, and others as above, but with an extra -25% for a thoroughly passive pose: no attacks or even active defenses! (Put some heavy DR or spines on your back to resist the beating.)

For most creatures with four limbs, one head, and vitals [total 9] to protect, Curling means a final 4 points (-10% retract all equally, -25% unsealed retraction, -25% for curling) for fairly good protection, or 2 points (-10% retract all equally, -50% half way retraction, -25% for curling) for lesser protection.

Dropping limbs

A great gag at parties:

Autotomization (new)

4 points

You can "drop" appendages, a drastic way to free yourself, confuse a foe, or lose an injured limb. The action is voluntary, and some pulling is required. Take damage equal to half the appendage's HP, rounded down, or only one-fifth its HP if it's is already crippled (or you have No Vulnerability: Blood). But the wound "seals" right away, making the ability an effective way to stop limb bleeding. (See Non-vital Appendages for safer Autotomization.)

You suffer all appropriate crippling effects for loss of an appendage. If your IQ is 4 or less, dropped appendages will squirm grotesquely for several minutes. Note that it's all a one-shot trick if you don't buy some Regeneration!

Cost is 1 point per appendage, up to 4 points for all. (Adjust cost if only some appendages can be dropped, per Modified Appendage HP.) Add 1 point to total cost if no physical force is needed – you can drop an appendage with just a thought!

Generic Appendage Modification options: none; modified Appendage HP; Retraction; Autotomization; Non-Vital Appendages; Injury Intolerance.

Natural Weaponry

A wide variety of natural weapons is detailed on CI p. 66.


Strikers are detailed in CI on p.66. Variations – horns, spears, etc. – combine generic strikers with claws (below).

Strikers (revised)


You have appendages that can strike forcefully.

Basic cost: A generic striker costs 5 points and does thrust/crushing damage. By default it has the Reach of an arm two Size levels shorter, i.e., a half-length arm (Reach C).

Extra Reach: Increase reach at half cost of Long Arms: 2 Size levels of length for 5 points. A total of 10 points buys a striker with a one-hex Reach, 15 points a 2-hex striker, etc.

Reduced cost: Buy the first two strikers at full cost, the next two at x1/2 cost, the next four at x1/4, the next eight at x1/8, etc.

Modified ST and DX: To increase striker ST or DX, use the same modification costs for one arm. But to decrease a striker's ST, subtract 10% of the cost of the striker and any Extra Reach for every -20% ST or every -1 DX. Any combination of ST or DX reduction that results in -100% cost removes all striking ability from the appendage.

Kickers and punchers: A striker can be a "puncher" (does less damage) or a "kicker" (does full damage, but has -2 DX, other "leg-like" limitations). For either of these, halve the cost of the striker and its Reach – but the maximum reduction in cost is 5 points. For example, 5-, 10-, 15-, and 20-point strikers would cost 2.5, 5,10, and 15 points, respectively, as punchers or kickers.

Manipulators: If it manipulates, buy an arm instead of a striker. Add 5 points to an arm that inflicts striker damage instead of puncher damage.

Grabber: The striker does no damage but can "grab". Use the cost of a kicker or puncher. This is cheaper than an arm with its manipulator, or a striker with a "No Manual DX" manipulator, but it's less versatile too.

The grabber may not perform fine manipulation, turn knobs, squeeze, hold weapons, or anything of the sort. It can only latch on to objects via a sticky surface or some sort of very primitive gripper.

Roll DX to hit; target may defend normally. Use the appendage's lifting ability, Contests of ST, etc. to determine what happens after that. Go ahead and roll strike damage for knockback purposes only; the force may knock a target off its feet, making it easier to reel in.

Zapper: This is 0-point option for any form of striker. The striker cannot perform crude manipulation or even support itself and wave about. You can only shoot it outward and instantly reel it back in, taking a turn to "ready" the striker (a free action, but halving attack rate). On the other hand, the zapper strikes exceptionally quickly: targets defend at -2.

Tails: Strikers can be integrated into tails; as noted under Tails, add the cost of the striker to the cost (if any) of the tail, with a -10% on the cost of the cheaper of the two.

Direction: For no cost, your striker may work in your rear and side hexes instead of your front hexes. (That doesn't mean you can see back there to strike effectively!)

Head Weapons

A default head has a weak bite and can butt (MA p. 50). The latter has little effect without training; it's a special effect if your physique doesn't allow it.

Add sharp teeth or fangs for weapons, or pay 5 points to buy the head as a striker, which hits on a DX roll and does thrust/crushing damage. Add horns (Claws) if you like, or increase Reach as a striker (see Long Neck).


See CI p. 67 for four types of Claws. In GURPS the trait affects all limbs, but GULLIVER tweaks cost and allows mixing and matching:

Claws (revised)


Claws may be added to any arm, leg or striker, and come in the following types:


Base Cost


Blunt Pincers (new)


+2 to crushing damage from grip

Sharp Pincers (new)


As Blunt Pincers, but damage is cutting

Blunt Claws (new name)


+2 to striking damage

Sharp Claws


Convert striking damage to cutting

Spear (new cost)


Thr+1/imp (thr-1/imp for punchers)



Thr/imp, sw/cut (thr-2/imp, sw-2/cut for punchers)

Long Talons


Thr+2/imp, sw+2/cut (thr/imp, sw/cut for punchers)

Cost: The base cost buys Claws for only two appendages. Pay the base cost for your most expensive set of Claws, and 10% of base cost for each additional pair of clawed appendages, which can be the same type or cheaper.

To buy only one clawed appendage instead of two, reduce the base cost by 20% (a small reduction, but only one attack per turn is the norm anyway).

Damage: Start with the appropriate thrust or swing damage for the appendage in question, whether puncher, kicker, or striker, before adding damage modifiers for claws. For example, damage starts at thrust -2 for a puncher, thrust for a kicker. Blunt Claws would do thrust damage on a puncher, thrust +2 on a kicker.

Special effects: Claws on feet may require special shoes, and subtract 1 from Stealth skill when barefoot.

Appropriate shaped claws help you grip and add to Climbing skill (see Book 4). Buy additional bonuses to Climbing (max +5) for 2 points per +1. (That also gives you a cost for tiny claws that do no damage but help you climb.)

Enhancement: Your claws retract. This lets you save them for "surprises", and removes Stealth penalties and the need for unusual footwear. +10%.

Claw types

Pincers are new: hard, ridged surfaces on hands (or the equivalent) that increase damage from grip when choking or crushing, like a lobster's large claw. Sharp Pincers are a lobster's small claw, or scissors!

GURPS' Small Claws have been renamed Blunt Claws, as befits their effect. They're perfect for rounded horns, hard hooves or heavy knuckles.

The base cost for Spear is derived from the CI write-up. It seems a superior advantage to 25-point Sharp Claws; 35 points may be a better cost.


Increased Reach on a striker with claws can represent a longer striker, or longer claws. A herbivore with a striker head [5], Reach boosted from C to 1 [5], and Blunt Claws [15] could have a long neck with small horns, or a normal neck with very long horns. The latter makes the striker less flexible, but the long horns can be used in ways a long neck can't (even to parry attacks!), and won't harm the creature if lopped off. Call it a 0-point choice. Lengthening claws in this manner doesn't increase damage.


Example: A Gargoyle has Talons on her two hands [40]. Additional Claws for two feet would cost 4 points for Talons, 2.5 points for Sharp Claws, or 1.5 points for Blunt Claws. To have Long Talons for the feet, start over: pay the full 55-point cost for a pair of Long Talons, and only 4 points for the arms' regular Talons.

Example: Your multi-armed insectoid has huge horns, more moderately clawed hands and feet, and a nasty stinger. You buy both the head and stinger as Strikers [5 points for the head to have Reach C, 10 points for the stinger to have Reach 1]. Now you take 55-point Long Talons for the horns – but a head's only one appendage. You could stick the remaining set of Long Talons on the stinger, but let's go with the head alone. Reduce the cost by 20% to 44 points for the one-appendage-only limitation; no more Long Talons can be added. For the stinger, you add a Talon for 3 points [4 points minus 20%, for only one appendage instead of a pair]. You equip four more limbs with Blunt Claws, this time in pairs [1.5 points per pair]. Total cost: 50 points.

Example: A rhinoceros' horn is a head-based Striker [10 points for Reach 1] with a Spear [25 points, -20% for one appendage, or 20 points]. The extra Reach goes in the horn, not the neck [0]. Total cost: 30 points, the same given in CI as the cost of a Spear.

Example: Your four-armed horror creature has scissors-like hands that can snip, stab or slash. Try buying Talons and then Sharp Pincers, combining them on the same appendages: 40 points for Talons on the first pair of hands, 4 points for Talons on the second pair, 1 point for Sharp Pincers on the first pair of hands, and 1 point for Sharp Pincers on the second set. Total cost: 46 points.

Other Mundane Weapons

Constriction Attack, Spines, Teeth, and Venom are common weapons.

Let Constriction Attack cost 5 points per appendage that can constrict (including the body), with cost decreasing as for limbs after the first two constrictors. A snakeman might spend 5 points on his Single Leg, 5 points on the rest of the body (increasing "wrap length"), and 2.5 points each on two flexible arms, for 15 points.

Bioelectric Shock exists in some fish. It would have an area effect underwater, perhaps with full effect in the user's hex, and damage halved each further hex.

The Smoke advantage (underwater only) models the ink clouds of octopi perfectly; call that a -30% limitation unless it's an aquatic campaign.

Webbing is a natural for spiders. Presumably the advantage includes the ability to walk on webs without sticking, but you can still be wrapped up and bound in webbing by a foe. Webbing lets you weave a small web only (CI p. 71); a skill Webweaving (P/E) might let you spin larger webs, as well as funnels or other specialized designs.

Mundane Weapons options: none; Strikers (striker; puncher; kicker; grabber); Extra Reach; Claws (Blunt Pincers; Sharp Pincers; Blunt Claws; Sharp Claws; Spear; Talons; Long Talons); Constriction Attack; Spines (Short Spines; Long Spines); Teeth (Blunt Teeth; Sharp Teeth; Fangs); Venom; Bioelectric Shock; Webbing; Smoke (ink: underwater only).

Exotic Weapons

GURPS offers the following choices on CI p. 72 under "Natural Attacks", as well as Involuntary Dampen from p. 102.

Exotic Weapons options: Bite; Breathe Fire; Cool; Dampen; Involuntary Dampen; Deafen; Flash; Image; Laser; Lightning; Shock; Smoke; Sonic Blast; Surge; Warm.

Head Modifications

Most head modifications are well detailed in GURPS: strikers (horns), teeth and fangs, sensory modifications, and so on. Below are a few more:

Basic Head Design

In game terms, a head is just a base for some sensory organs, a mouth, and maybe a couple of other accouterments. Call a head a 0-point effect, giving a little more mobility to whatever you put on it, if not appreciably more Reach (but see Long Neck). GULLIVER also suggests that non-leg appendages, including heads on mobile necks, gain some defensive advantages. That's another reason to put good stuff on a head.


Lots of primitive creatures are headless. This isn't a single trait; build it as appropriate. No Vulnerability: Neck works, and so do No Vulnerability: Brain (CI p. 58) and No Vulnerability: Eyes, unless these features are located elsewhere.

Other options come to mind, including Deafness, Anosmia, Mute, and No Bite, very low IQ, and serious social disadvantages. Zero-point effects include no headbutt ability and a loss of height, mixed with immunity to headlocks and neck snaps.

Multiple heads

Use multiple heads to build a Hydra or Cerberus. A chimera mixes different types of heads.

Extra Heads (revised)

20 or 70 points per head

Each Extra Head adds one level of Alertness and the effects of Independently Focusable Eyes, for 20 points. (Each conscious head can focus on a different target in combat; if an individual head's eyes happen to be individually focusable, buy the trait normally.) The 70-point version adds a level of Compartmentalized Mind.

By default the heads' brains are independent of each other as far as injury is concerned. Damage multipliers for the brain count normally, but a brain can take at most (HPx2 divided by number of brains) damage. (Assume that each head itself can only take up to HP damage before becoming inoperable; like a limb it causes you no more overall HP loss, unless the brain is targeted and can still take more damage.)

Always treat the final head normally in all respects: damage to it accumulates with no limit. Head blows can stun or knock you out normally, and if that last head "dies", you die.

To buy teeth, necks, and other advantages for heads, use a version of the Claws rule: pay full cost to have any advantage on one head, and 10% cost for each additional head.

Disadvantages (weak jaws, etc.) should cover all heads automatically. If some heads have the disadvantage and some don't, adjust the value accordingly (halve value if only half of your heads are affected, etc.).

Limitation: Your brains are not fully independent. Roll vs HT at +4 when a brain is stunned, +0 if knocked out, and -4 for devastating injury; add +2 for each remaining conscious brain. Failure means other heads are stunned, or knocked out if the roll fails by 4 or more and the injured head was also knocked out. Roll separately for each head if you like. Also, each brain will take up to (HPx4 divided by number of brains) damage; treat the last one normally. -10%.

Limitation: As above, but brains are even more connected in function. HT rolls above are at -2, and each remaining conscious head adds only +1 to the roll. Loss of a brain reduces IQ by (6 divided by total number of brains, round up), and loss of half or more of your brains adds the Hard of Hearing disadvantage. Each brain can take up to (HPx6 divided by number of brains) damage. This is best suited to the cheaper form of Extra Heads. -20%.

Head Size

A default head's height is about one-sixth the body's (or one-eighth for Supers). Call them all -5 TH and don't worry about minor variations. But for creatures with really odd-sized melons:

Large/Small Head (new)

0 points/level

Each level of Large or Small Head adjusts head Size by one level. That affects its size as a target, but free skull DR scales accordingly. Each level also includes a level of Large or Small Eyes and Large or Small Mouth.

Example: A Size +2 buffalo with a level of Large Head has a head 3 Size levels above the human default. Scale free skull DR using Size +3, or Linear Scale x3, for DR 6. In combat, head, eye, mouth, and brain targets will all be +3 to hit over human TH modifiers.

Also see Brain Size. A smaller head requires a smaller brain, but a larger head doesn't necessarily mean a large brain!


Making a head a striker costs 5 points.

Basic Head Design options: number of heads (headless; one head; Extra Heads); head size (Large Head; Small Head); sensory modifications; weaponry.


Injury tolerance

A neck is just another appendage, with a head on the end – which can mean important passageways run through. No Vulnerability: Neck buys these off: say, 2 points for vulnerability to suffocation through choking (overlaps with Doesn't Breathe), 1 point for vulnerability to extra damage through strangling, and 2 points for the lifeline to important head stuff (cutting attacks do extra damage, and severing the neck kills you; overlaps with No Vulnerability: Brain).

If you care for the extra detail, adjust the cost of combinations of No Vulnerability traits whose effects overlap as above.

Even if you can't be choked, you may still have air intakes that can be covered to suffocate you; see Respiration.


A long neck lets you take in the view from on high, snorkel underwater, and reach far to bite or head butt.

Long Neck (new)

2.5 points per level

Long Neck is Increased Reach for the head, using the cost of Reach for strikers. Default Reach for a neck is C; each level increases this by one Size level. Two levels get you a neck with a Reach of 1, four levels a Reach of 2. If you have multiple necks, decrease cost as for other appendages.

Waive the cost for Long Neck if the head carries nothing of interest – no mouth, no striking ability, no sensory organs, no airways to let the neck act as a snorkel, etc. You've just got a long ugly lump that you insist on calling a head.

A short neck is a special effect, unless it can't be targeted in combat (No Vulnerability: Neck) or can't turn (see Stiff Neck under Inflexible Body).


See the earlier discussion of Flexibility for Flexible Neck.

Neck options: number of necks; injury tolerance (No Vulnerability: Neck); neck length (No Vulnerability: Neck; Stiff Neck; normal; Long Neck).


Head brain

Putting a brain in a head makes the head and neck especially vulnerable targets. As a consolation, the head gets free DR 2 to protect the brain, and GULLIVER suggests improved AD for mobile appendages like heads. It's a 0-point tradeoff.

Adjust free brain DR for Linear Scale, for no cost. A Size +2 Giant has free DR 4 on the brain, and a Size -2 dog has only DR 1. (Additional DR works normally: adding a point of overall DR adds DR 1 to the brain for any creature, the same as it adds to the body.)

Body brain

A brain in the body gets no free DR but has other protection (see Retraction for rules on targeting things buried inside).

While your neck is no longer a vital lifeline (see No Vulnerability: Neck), the brain's surrounding area will still be full of vital support systems. Let any damage that hits the brain area, but which is taken by body HP, cause extra shock as a jaw attack if crushing, or extra damage as a neck attack if cutting.

That leaves a body-held brain about as vulnerable as one in a head, for 0 points.

Injury tolerance

No Vulnerability: Brain means your brain (if any) isn't particularly vulnerable to injury. Blows do no extra damage. Allow a reduced version for 4 points: brain blows only have 2x, not 4x, their normal effect (alternately, treat them as blows to vitals), and HT rolls to avoid effects of head/brain blows are at +4.

You can break down No Vulnerability: Brain by what it buys off: 2 points for the 4x brain damage multiple (only 1 point for a lower multiples as above), 1 point for extra stunning to surrounding areas (nose, jaw, etc.), and 2 points for the vulnerability of the lifeline to the brain (overlapping with No Vulnerability: Neck).

If you care for the extra detail, adjust the cost of combinations of No Vulnerability traits whose effects overlap as above.

Multiple brains

With multiple brains, each can contribute up to (HPx6 damage divided by number of brains) to total HP loss. See Extra Heads.

Multiple brains are less helpful than No Vulnerability: Brain. Pay 2 points for two brains, 3 points for three, and 4 points for four or more, for the extra injury tolerance. Pay separately for things like Independently Focusable Eyes, Alertness, and Compartmentalized Mind. Non-independent multiple brains can also take the limitations under Extra Heads.

Brain Size

Allow Large or Small Brain, affecting target size but also damage-taking ability. Brains don't actually have HP, so adjust damage as appropriate for the brain's new "Linear Scale". Large Brain +4 divides brain injury damage damage by 5; Small Brain -2 multiplies damage by 2; etc.

Brain options: location; injury tolerance (No Vulnerability: Brain); number of brains (No Vulnerability: Brain; one brain; Extra Brains); brain size (Large Brain; Small Brain)


The default "herbivore mouth" combines a very weak striker (see CI p. 67.) with limited grabbing and holding ability. Price it as a default striker [5 for Reach C], included for free in the default creature.

The ability to eat through the mouth is a 0-point freebie; it's useful, but introduces a vulnerability to swallowed poisons as well.

Sharp teeth

In addition to Sharp Teeth [5] and Fangs [10], add Large Teeth [2]. Damage is crushing, but use full Combat ST with the table on BS p. 140, not half ST.

No Mouth

Take No Mouth [-5] and possibly Mute. You can't bite and have some other means of eating.


Hagfish and lampreys are agnathan, having a mouth with no jaws. Let Can't Close Mouth be a -1 point disadvantage, and add Mute, OPH (drooling), and other nasties as options. Stay away from wiseacre PCs with grenades.

Mouth Size

GURPS places a mouth or nose at -6 TH – only slightly smaller than the entire head! A Size of -8 or so is more realistic as a combat target; see notes in Book 5.

Scale mouth size with head size. (A bigger mouth does not automatically have higher biting damage; that still depends on ST.) But many creatures will have jaws out of human proportion:

Large/Small Mouth (new)

0 points/level

Each level of Large or Small Mouth adjusts the Size of the mouth/nose/jaw region by one level, affecting its size as a target. A larger mouth is good for snapping at tiny targets (see Book 5 rules for large weapons vs small targets). Also scale eating speed by the mouth's Linear Scale.

Limit Small Mouth to five levels, at which point you're barely sipping food through your tiny cake hole. Most animals have Large Mouth: a monkey has one level, a cat two, a wolf three, a frog or Tyrannosaur four, and a Dune sandworm five, also a limit. (Even starting at -8 TH, four or five levels of Large Mouth means a mouth with Size larger than the head's. That's okay; think of an alligator's giant snout, bigger than the rest of its nut.)

Mouth Reach

A mouth gains the Reach of the head (or other appendage) it's placed upon.

If your large mouth is a long snout or beak, not just a big hole, buy Extra Reach as a striker. (See Book 5 rules for clamping a gator's long muzzle shut.)


Build an insect's snapping mandibles with enhanced teeth damage, Large Mouth, and possibly Extra Reach.

Modified Jaw Strength

Biting damage is based on Combat ST. Purchase additional ST (Jaws Only) for 10% the cost of full ST. (ST is very cheap at high levels, though; charge a minimum 5 points per +1d added if this is a problem.)

Reduced ST (Jaws Only) uses a different scheme: -20% ST for -1 point. For -5 points you have no meaningful jaw ST ("Applesauce? Again?") and No Bite.

Throat modifications

A human design flaw ties eating, breathing, and speaking to the same opening. We choke on food, can't speak when out of breath, and look bad when orating through meatloaf.

For 1 point, only two of those three functions are tied together; the third (your choice) is separate. (For breathing, this is Separate Respiratory Intake.) For 2 points, all three functions are separated and do not interfere with each other. This advantage is likely to come from separate "mouths" or other organs for each function, but could just mean the passageways have safeguards against interference.

One-Way Jaws

Your teeth point inward like the barbs of a hook, or you have a tremendous peristalsis action with no shutoff. You have a +5 on Contests to keep foes in your jaws from breaking free, but at the same time, you have to eat what you bite, never mind that it just pulled the pin on a frag grenade. Bon appetit. This is a 0-point effect.

Tongue modifications

A tongue is generally of no consequence in game terms, even if it hosts real-life abilities such as Discriminating Smell. For bizarre tongues that can grab or pummel objects, use appropriate combinations of strikers, Retraction, etc.

Example: You have a tongue like a frog's. This is a "grabber" striker with two-hex range and -60% ST [10, -60% = 4], the Zapper option [0] and Retraction [1]. Total cost: 5 points. If you can normally talk, add a -25% Nuisance Limitation: Mute while using the tongue.

Multiple mouths

For simplicity, additional default mouths are free. Add Extra Reach and other traits as you would for strikers. Add enhanced teeth using a version of the Claws cost: Pay full cost for the most expensive set of teeth, and 10% cost for additional sets of the same or less expensive teeth. (This is separate from actual claws; claws and teeth don't affect each others' cost.)

Mouth options: number of mouths (No Mouth; one; Extra Mouths); mouth size (Small Mouth; normal; Large Mouth); bite modifications (No Mouth; Modified Jaw Strength; Sharp Teeth; One-Way Jaws); Can't Close Mouth; tongue modifications.

Other Appendages


Tails are -3 to be hit by default and have HP of HP/3. A large, thick tail is at least half your length and has HP of HP/2, but is only -2 to be hit; this is a 0-point effect. Tails by default are flexible.

Tails that don't do anything special are worth no points. But they do add important functions in real animals:

Tail (new)

varies (package)

A tail may add specific benefits, which are lost if the tail is crippled:

balance: Buy Improved Balance. One level requires a tail with minimum length of one-quarter overall length. Double minimum length for each additional level of Improved Balance, up to +4 max.

other skills: A tail can aid Flight, Swimming, Acrobatics, or Jumping. Cost is 2 points per skill per +1; as with Improved Balance, a given bonus requires a minimum tail length.

Striker: Purchase the striker normally. This gives you a creature with both a tail and a nifty, separate striker; to integrate the two into one appendage, add the costs for the tail and the striker, with a -10% limitation on the cheaper of the two. A tail striker will usually attack rear hexes only [0].

counterweight: You have a large tail (see stats above) that acts as an effective counterweight, aiding balance and quick full-body movements. Purchase an additional point of racial DX, with a -30% limitation: Athletic Skills and Rolls Only (including balance).

If you're a two-legger and buy a counterweight and any level of Improved Balance, you get a free bonus: you can stand and walk in a nose-to-the-ground pose that would otherwise tip you right over.

Limitation: The counterweight is extremely important to your stability. If crippled, you lose the tail's +1 DX bonus – and in addition suffer two levels of Poor Balance (or lose the same levels of Improved Balance). Net -50% cost of DX.

Tail options: none; tail effects (Improved Balance; skill bonuses; Striker; counterweight).

Skin and Hide


See notes on DR and Toughness. Fur and Hide or Scales are CI options that combine DR, PD, and Temperature Tolerance.

DR, part by part

Use the Modified Appendage HP rules to buy DR part by part, breaking up its cost as follows:

Those percentages can work as limitations on your total cost of DR. If your head has only half the DR you have everywhere else, buy half your DR at full cost, and half with a -20% limitation (Doesn't Affect Head).


Passive Defense represents the ability of armor to make blows "bounce off" or otherwise miss (perhaps "turning" them magically). It's not a good way to model protection due to quick speed or small size! Remember that PD protects equally against fists, lasers, and razor-sharp battleaxes, and works even if the creature is unaware of attack, or is unmoving. There's no reason why a laser should reflect off a sleeping Ellyl.

Instead of Passive Defense, use a boost to Active Defenses (from negative encumbrance or Increased Speed) to model quickness, and simple size-based TH modifiers to model an Ellyl's small target area.

To customize PD by body part, borrow the rules for part-by-part DR.

Armor options: normal; DR; Ablative DR; Toughness; Passive Defense; Spines; Fur (very thin fur; fur; thick fur; spiny fur); Hide or Scales (very light scales; scales; thick hide; heavy scales; carapace; armor plates).

Other Skin Modifications

Fur and feathers are good for one or two levels of Temperature Tolerance, as is a layer of fat under the skin. Thick blubber might be good for three or more levels.


A common trait in low-lifes:

Slime (new)

2 points/level

You ooze mucus. Slime confers a +2 to escape holds, pins, snares etc., and each level acts as 2 points of ablative DR vs heat and flame attacks and DR 1 vs abrasion-type damage (i.e., you can slither over gravel without scrapes). Fish also use mucus to reduce water drag (see Book 4). Limit Slime levels to 4 times your Linear Scale.

If you have a Dependency on moist skin, Slime extends your "safe time" for as long as it stays moist. Each level also increases your water intake requirements by 10%, as your body works to maintain your slime. Assume you stay slick in very damp air, but lose a level every three hours in normal humidity, every hour in dry air, and every 30 minutes in desert-like air (every 10 minutes if it's also hot and sunny!).

Sliming back up requires damp air, lots of water to drink, and one hour (halved on an HT roll) to regain each level of Slime. Divide this time by three if you're immersed in water.

Limitation: Your slime doesn't replenish by itself; you dry out twice as fast, and need to enter water as above to "slime up" (don't divide time required by three). On the plus side, halve the extra water intake requirements. -25%

Enhancement: Your slime replenishes itself very efficiently. You dry out only half as fast and replenish twice as fast – but double your extra water intake requirements. +25%. Or, you dry out only one-fourth as fast and replenish four times as fast – but quadruple your extra water intake requirements. +50%.

Other Mundane Skin Modification options: normal; Temperature Tolerance; Albinism; Chameleon; Slime; exotic (Elastic Skin).

Miscellaneous External Effects


Set appearance as you like; traits chosen so far may suggest modifications. (Do your Large Eyes make you look adorable, or just freakish?) As always, appearance modifiers should be relative to some campaign norm. Modify costs if appearance affects only certain groups in the game.

Very Attractive

Add Very Attractive as a new appearance level between Attractive and Handsome/Beautiful. It costs 10 points and gives +1 on reactions from the same sex, +3 from the opposite.

Warning colors

Many creatures are aposematic, using garish colors or confusing patterns that say "leave me alone". Use a bonus on reaction rolls, but with a limitation: Combat Reactions Only (including Intimidation rolls) [-50%]. Also adjust for the size of the natural enemy group affected.

A generic "mean" or "dangerous" look serves the same purpose even in human PCs, probably affecting a large group.

Appearance options: Monstrous; Horrific; Hideous; Ugly; Unattractive; human norm; Attractive; Very Attractive; Handsome/Beautiful; Very Handsome/Very Beautiful; special (Scalped; Unnatural Feature); Reaction bonuses (Combat Reactions Only).


Camouflage is a form of passive mimicry. The Chameleon advantage is an exotic effect that lets you blend into any background. For a realistic ability, cut the cost to 5 points per level and call it Camouflage. It works only in specific environments (jungle, snow-field, underwater), or allows simple color changes (like green to brown). Reduce cost to only 3 points per level for one specific background (wood/bark, leaves, rock) or very simple color change (dark green to dark brown). All of these are common in nature.

You can also look like something dangerous or untasty, a ruse called Batesian mimicry. Use the rules for warning colors, and don't let on that you're actually the buttery-sweet cousin of your foul-tasting look-alike.

Active mimicry abilities include the Mimicry advantage (letting you sound like someone else), Elastic Skin, and Morph.

Mimicry options: Reaction bonus (Combat Reactions only); Camouflage; Mimicry; exotic (Chameleon; Elastic Skin; Morph).


Easy to track

This trait deals with what you leave behind when you move. It could easily be an effect of your skin or your body odor.

Obvious Trail (new)

-5 points

You leave a trail behind that no one could miss – a slick of goo, a glowing air trail, even the proverbial swath of destruction. Pursuers' Tracking attempts generally succeed automatically or roll at +10 if there's any reason an attempt might miss. Divide any negative modifiers to the Tracking roll (for age of tracks, your skill at hiding tracks, etc.) by 5.

Or buy the trait in levels: each is worth -1 point and adds +2 to foes' tracking attempts. Negative modifiers are still divided by 5 as above.

Limitation: Your trail is obvious only to sight-based trackers (-40%) or to scent-based trackers (i.e., trackers with Discriminating Scent, -60%). This reduces the value of the disadvantage.

Limitation: Your trail is obvious to only members of your own species, or another select group. -40%. Other groups can still detect it normally, without the bonuses.

Enhancement: You leave an obvious trail only when you want to. Turn the base disadvantage value into an advantage; you mark your path effortlessly whenever you like. Treat the above limitations as zero-point effects if they always apply to your trails; treat them as enhancements if you can turn them on and off as well.

Example: Ants mark food trails with a chemical scent. This is a selective trail, so it's worth 5 points as an advantage, with the zero-point effects "scent-based" and "ants only". But if ants could select whether to make the scent obvious to ants only or to anybody, that'd be a +60% enhancement.

Hard to track

The opposite is Hard to Track:

Hard to Track (new)

5 points

Pursuers suffer -10 on attempts to track you. Or use levels: 1 point per -2 on foes' Tracking.

The GM can cut trackers' penalties sharply if you've eaten strong food, stepped in smelly stuff, handled items touched by others, and so on.

Limitation: Your ability is effective against one group only. -40%.

Limitation: You're inobvious only to sight-based trackers (-40%) or scent-based trackers (-60%).

Enhancement: You can turn off your ability (just in case you want to leave normal tracks). +20%.

Example: Your race produces very little odor. That's worth 5 points with a -60% limitation (scent-based only), or 2 points.

Trails options: Obvious Trail; none; Hard to Track.

Sound Signature

Trackers can also find you by sound. Normal walking gives listeners a hearing roll to detect you; use Stealth to move more quietly. No movement should be good for a +5 or so. Size and other factors affect things; see Book 4. These are 0-point, default modifiers.


If you're exceptionally noisy, use a leveled "Loud" disadvantage: each level is worth -1 point and gives listeners a +2 to hear you when you move. At the max 5 levels, you may have a hard time hearing yourself think!

Reduce value if the sound only accompanies one form of movement: your wings buzz in flight, for example.

Add 50% to the value of any levels that make you noisy even standing still, and +100% to the value of any levels that can't be silenced even by sleep!


The opposite of Loud is Silence (CI p. 66). Silence makes all your movement quieter. Reduce its value if it only works in one mode of movement.

Sound Signature options: Loud; none; Silence.

Senses: General

Alertness is the "meta" advantage that aids all senses.

Senses and Environment

By default, you can see and hear equally well on land and in water, subject to the peculiarities of each. If your senses are diminished in a non-Primary Environment, use the one-fifth value rule. A fish has a -5 point disadvantage (-25 x 1/5) if it's nearsighted out of water. A human gets -2 points for nearsightedness in the water (-10 x 1/5; it's correctable with goggles). The latter is presumably ignored in humans' point cost.

Correctable Problems

Bad Sight includes two costs: the standard base cost and a lower cost for a correctable condition. You can extend this to a cost modification for any appropriate sensory disadvantage. (Bio-Tech calls this Mitigation.)

Reduce any sensory disadvantage value to x2/5 for availability of standard correction measures which can be lost easily (glasses) or present comfort and care difficulties (contact lenses). Reduce value to x1/5 for smaller, more trouble-free measures (a button-sized hearing aid). Remove the disadvantage entirely for trouble-free correction (a high-tech bionic eye).

Extending Range

Antennae are appendages that extend the reach or function of senses, often taste/smell and touch. Long ones might be worth points:

Antennae (new)


Antennae extend the reach or function of sensory organs. They have HP equal to total HP/5 (or HP/4 if two hexes or longer), and can be targeted at -6 TH. Antennae cannot manipulate, strike, or grab; if they can, buy them as arms or strikers.

The appropriate antennae can let you extend an eye or ear cautiously over a wall, or cautiously probe an unusual food from a distance. Losing a feeler to a suspected trap is better than losing a hand, and a poison "tasted" through feelers instead of the mouth will have reduced effect, GM willing.

Very short antennae are a 0-point effect. But a pair that extend sensory range to Reach C cost 1 point per affected sense (treat taste/smell as one). Charge 2 points for Reach 1, and an additional 1 point per extra Size level of Reach. (Adjust Reach for your Linear Scale.)

Long stalks also make your sensory organs vulnerable. If loss of the antennae would bring about some serious disadvantage, add 10% of the disadvantage cost to the cost of your antennae. If the antennae add some ability – Keen Hearing, Faz Sense, Sensitive Touch, etc. – take a -10% limitation on the cost of the advantage. Loss of the antennae removes the ability.

Example: Your antennae have Reach 3 [4] to extend your sense of touch, and also act as ears. Their loss doesn't remove your sense of touch itself, just its extended range; there's no disadvantage value there. But their loss gives you Hard of Hearing, worth [-10, -10% = -1]. Their net cost is 3 points.

Example: Eyes on short stalks cost 1 point. They're good for peeping around corners, but are vulnerable to enemy attacks. Add 10% of the value of Blindness: -5 points, for a net -4 points. If your eyestalks also add Peripheral Vision, buy the trait with a -10% limitation for vulnerability.

Skin-based Senses

Skin is the organ of touch, but it (or cilia covering it) could conceivably host other senses.

Whole-body hearing offers no big functional advantage over ears. Whole-body taste/smell is a mixed bag, useful at times but also exposing you to additional nauseous flavors and odors. Only whole-body sight offers a clear advantage: 360-Degree Vision.

Skin-based senses are hard to neutralize. Use No Vulnerability: Eyes, No Vulnerability: Ears, or No Vulnerability: Nose, with a -50% limitation: Blocked by Worn Items. Clothing and the like create covered "blind spots"; game appropriately. One-quarter coverage might reduce skin-based sight rolls by -2 and half coverage by -4; full coverage blinds. Treat hearing similarly, but halve effective coverage unless it's exceptionally thick. Mesh-like coverage affects any sense very little. And so on.

General Senses options: none; Alertness; points of sensory contact (humanlike organs; Antennae; skin/cilia).

Senses: Vision

Eye Structure

Eyes have "free" HP 2 by default. Scale HP with Linear Scale, as a no-cost part of the Size trait.

Single Eye is an eye that functions like two (just as Single Leg is a leg that functions as two). GURPS' One Eye [-15] breaks down as Single Eye [-2], No Depth Perception [-10] and a negatable reaction penalty [let's say -3].

Nictating Membrane is useful (though expensive), as are Independently Focusable Eyes. The latter is reworked below, as are Peripheral Vision and 360-Degree Vision.

Eye placement is important. Narrow, straightforward placement makes Peripheral Vision a difficult purchase (or even creates No Peripheral Vision). Humans, apes, and owls have "normal" front placement. Animals often have wide eye placement with Peripheral Vision; eyes on opposite sides of the head further add Triangulated Depth Perception.

Eyes all around the head or eyestalks can confer Peripheral Vision or 360-Degree Vision. Replace the Eyestalks limitation on CI p. 68. with the Antennae rules.

No Vulnerability: Eyes (new)

5 points

You see normally and cannot be blinded. This may be due to magical eyes invulnerable to harm, or eyeless sight coming from unnatural senses. No Vulnerability: Eyes is cheaper than Nictating Membrane, but isn't appropriate for "natural" designs.

Single Eye (new)

-2 points

You have a single eye with normal (presumably magical) depth perception. Add appearance or reaction penalties separately if appropriate. The disadvantage value covers the fact that you're blind after losing only one eye; it's a tempting target for foes with pointy things. Single Eye replaces Cyclops on FF p. 73.

Lidless Eyes (new)

-3 points

Your eyes do not shut. A Flash attack affects you normally, but you can't close your eyes to protect against additional attacks. Constant bright light will affect you abnormally, and snow blindness will set in three times as fast. Blowing dust or sand will present great difficulty unless you have Nictating Membrane. Other problems are as the GM determines.

Large/Small Eyes (new)

0 points/level

Each level of Large or Small Eyes adjusts eye Size by one level. That affects target size, but let eye HP scale accordingly. A Size -3 creature with one level of Large Eyes has Size -2 eyes relative to human, for half human eye HP.

Limit either to 5 levels. (Combine Large Eyes with Single Eye, and you're just begging foes to sharpen some sticks...)

Extra Eyes (new)


Extra eyes provide backups. The cost is 1 point for three or four eyes, 2 points for five or six, and 3 points for seven or more. Peripheral Vision is likely; use 360-Degree Vision if the eyes are spaced around the head.

Independently Focusable Eyes (revised)

15 points/level

Your eyes can focus independently, allowing you to aim weapons at two or more targets at once. The first level affects your default two eyes; each additional level enables another eye (and includes the extra eye for free!).

Limitation: One eye on a target confers the penalties of No Depth Perception. You'll have to put up with that or buy enough levels to let you keep two eyes on each target. This is a realistic working of the advantage! -20%

Eye Structure options: eye number (No Vulnerability: Eyes; One Eye; Single Eye; default two eyes; Extra Eyes); eye placement; eye size (Small Eyes; normal; Large Eyes); Independently Focusable Eyes; Nictating Membrane; Lidless Eyes.

Vision Modifications

Build primitive vision systems with combinations of Bad Sight and other disadvantages below, using the Overlapping Disadvantages rule.

Modified peripheral vision

For vision purposes, you have a default 3 front hexes, two side hexes, and one rear hex. (How well you see into your hexes is separate from how well you can move into or fight in them. Modify hex movement as above, and attack/defense to rear and offhand hexes with Ambidexterity and flexibility traits.)

Pay 5 points to "upgrade" a side vision hex to a front hex, or a rear hex to a side hex. "Downgrading" a front hex to a side hex is worth -2 points, and a side hex to a rear hex, -3 points.

Peripheral Vision [15]: Two side hexes upgraded to front hexes, one rear hex upgraded to a side hex.

360-Degree Vision (new cost) [20]: As Peripheral Vision, but remaining side hex upgraded to front hex.

No Peripheral Vision (new) [-10]: You have a form of tunnel vision, seeing clearly in a 30° cone in front of you only. Downgrade your other two front hexes to side, and your normal side hexes to rear.

New traits

Here are some new ideas, primarily for reptilian and lower life forms:

Motion Detection Only (new)

-15 points

If it doesn't move, it doesn't register. Prey or a combat foe "disappears" into your surroundings as soon as it stops moving. Make an IQ roll each turn to "remember" which object was the moving one, at -1 for each turn it hasn't moved. Adjust for contrast: a lone, brightly-colored object gives a +4; a camouflaged object or a person "freezing" among a display of mannequins nets a -4 or worse.

Targets in your field of view need to win a Contest of Stealth vs your Vision to "freeze" and escape your notice; the Stealth roll is at -4 if the target wants to slowly reach for a gun...

Fine details escape you if they're not in motion. Vision rolls to detect nonmoving things of interest – the keys you dropped in the grass, an item missing from your desk – are at -4 or fail, as the GM determines.

Triangulated Depth Perception (new)

-5 points

You lack true binocular vision, but can compensate by observing parallax as you turn your head from side to side, like an octopus or many reptiles. Treat as No Depth Perception, but for each turn you Concentrate and succeed on a Vision roll, reduce skill penalties by one.

If you have any Vision enhancements whose use requires triangulation, take a -5% limitation on their cost.

Shape and Light Detection Only (new)

-40 points

You're nearly blind, seeing only shadow and vague, blurred shapes – no color or detail. You can strike out at -6 TH, but cannot aim at specific body parts (or even differentiate faces, so make sure it's not a friend!). You cannot read or perform close manual tasks requiring sight. Tasks like driving will suffer at least a -6 penalty or be impossible, as the GM decides.

Light Detection Only (new)

-45 points

As above, but you see only light and darkness; no shapes or color. Combat blows are made blind, or at -8 TH if the foe is detectable by how it blocks light. Most other visual tasks are impossible.

Light sensitivity

Below are traits dealing with sensitivity to light. Alternately, use the light rules from Book 6, under which the traits below make simple adjustments to light level.

Bad Sight (light sensitivity) (new)

-10/-25 points

Your eyes are sensitive to light. The higher disadvantage value applies if dark glasses are not available.

Bright sunlight or harsh artificial lighting gives you -4 on Vision rolls and -2 DX and IQ for constant discomfort. A shady area, cloudy day, or bright indoor lighting gives you -2 Vision and -1 DX and IQ. Ordinary indoor lighting gives no penalties. Anything dimmer than that, and you take normal penalties for darkness.

Lights that cause even normal folks penalties are a real problem. Quadruple any penalties for blinding light (though blindness is the worst you can suffer) and their duration. If any HT rolls are involved, you're at -4.

Heavy wrap-around dark goggles, welder's goggles, etc. negate the disadvantage, but you'll want to take them off in dark areas! Normal sunglasses reduce you to mild light sensitivity (below), but again are a hazard in the dark.

Limitation: You have mild light sensitivity. You suffer -2 Vision and -1 IQ and DX in bright light, and no penalties in normal light. You suffer only double, not quadruple, penalties and durations from blinding lights; related HT rolls are at -2. (Rewrite Albinism to include this if you like.) -50%.

Night Vision (revised)

5 or 10 points

10-point Night Vision removes any darkness penalties, as in GURPS. The 5-point version is more realistic: halve darkness penalties, rounding down. Neither version helps at all in total darkness!

Night Blindness (revised)

-10 points

You suffer double darkness penalties, as in GURPS. If the initial darkness penalty is -5 or worse, you can't see at all! Forget the "minimum" combat penalty, but even a slightly dim area – no penalty to a normal person – gives you a -1.

Mundane Vision Modification options: normal; Blindness; Bad Sight (nearsighted; farsighted; light sensitivity; mild light sensitivity); Color Blindness; Shape and Light Detection Only; Light Detection Only; Night Vision; Night Blindness; Acute Vision; modified peripheral vision (Peripheral Vision; 360-Degree Vision; No Peripheral Vision; other Modified Peripheral Vision); No Depth Perception.

Exotic Vision Modification options: none; Dark Vision; Infravision; Microscopic Vision; Polarized Eyes; See Invisible; Spectrum Vision; Telescopic Vision; 360-Degree Vision.

Senses: Hearing

Ear Structure

Number and size of ears are special effects. If huge ears help you catch sound, add Acute Hearing.

No Vulnerability: Ears (new)

2 points

You have normal hearing but can't be deafened; you're immune to sound-based stun attacks, ear claps, and so on.

Ear Structure options: size, shape and number of ears; No Vulnerability: Ears;

Hearing Modifications

Hearing in the subsonic or ultrasonic range only is a 0-point effect. Hearing in those ranges in addition to the normal range is an advantage.

Subsonic Hearing and Ultrahearing are not necessarily exotic; elephants can hear well in both the normal and subsonic ranges, as far as we can tell.

Directional Hearing

To model the hearing of humans and other creatures whose ears "face" one direction, take a +1 on rolls to hear sounds coming from your ears' direction, and a -2 on sounds coming from the opposite direction. In cases of doubt, use no modifier. Call this Directional Hearing a 0-point effect.

A particularly good ability to pinpoint the direction of a sound might be Acute Hearing with a -50% limitation: Direction Gauging Only. A particularly poor ability might be worth -1 point: you detect sounds normally, but require a Hearing roll to gauge their direction of origin (or take a -4 in situations when any character needs to make such a roll).

Mundane Hearing options: normal; subsonic only; ultrasonic only; Sonar Vision; Deafness; Hard of Hearing; Directional Hearing; Acute Hearing.

Exotic Hearing options: none; Parabolic Hearing; Subsonic Hearing; Ultrahearing.

Senses: Other


See Bunnies & Burrows for ideas on how important taste and scent are in the animal world!

No Vulnerability: Nose (new)

1 point

This is an odd Injury Tolerance. You have a normal sense of smell/taste, which can't be "blinded" by overwhelming stenches or flavors. Also take a +4 on rolls to resist nausea or other bad effects from these.

Taste/Scent options: normal; Acute Taste and Smell; No Sense of Smell/Taste; Discriminatory Smell; Discriminatory Taste; No Vulnerability: Nose.


Allow Acute Touch as a new trait, helping you feel a slight vibration, subtle temperature change, or shallow scar in a smooth surface. Cost is 2 points per +1. Sensitive Touch allows even more amazing ability.

How about the opposite? With a poor or no sense of touch you wouldn't feel pain, heat, cold, vibration, wind, or even the placement of your own limbs and the ground beneath your feet. It's possible that such a character would be a nonfunctioning wreck. Save the condition for plants, or try the following if you must:

Poor Sense of Touch (new)

-10/-20 points

For -10 points, you require a Touch sense roll to feel a stiff breeze, rough footing, a gun in your ribs, anything that'd be obvious to the normal person. You automatically disregard anything subtler than that.

For -20 points, forget the sense roll; you don't feel even obvious things. The only way you'll know you've been "touched" by something is by observing it or its effects.

Additional effects are only guesses. For starters, consider adding No Pain or Very High Pain Threshold, Klutz, Reduced Manual Dexterity or No Fine Manipulators, and a reduced DX. If you don't have enough sense in your limbs to feel the ground, add some level of Lame. (Note that normal people with two artificial legs can learn to walk, getting feedback through the points of contact with the prosthetics.)

Touch options: normal; Acute Touch; High Pain Threshold; Low Pain Threshold.; Poor Sense of Touch; exotic (Sensitive Touch).

Special Senses

Sonar, directional, and magnetic senses exist in real creatures. Exotic characters can sense magnetism, radio waves, and even "time". Faz Sense has real-world counterparts, such as the "lateral line" that helps fish detect motion. (In fictional races, the ability goes well with Antennae.)

A limited form of Absolute Direction might explain stories of cats and dogs showing up on the doorstep after journeying hundreds of miles: for 2 points, Absolute Direction functions only to give you a sense of the direction of one familiar location ("home"). For 3 points it's more reliable, like the sense of a homing pigeon.

Special Sense options: normal; Absolute Direction; Absolute Direction (normal; home only); 3D Spatial Sense; Faz Sense; Acute Faz; Field Sense; Magnetic Sense; Antennae; exotic (Absolute Timing; Radar Sense; Radio Hearing; Sense of Perception).


Mundane Communication

Mute removes your ability to speak, not to make sounds; you can still babble, howl, growl etc. normally for your species. Call that Mute (No Speech) [-25] and use a stricter variant for no vocal sounds at all: Mute (No Voice) [-30].

Vocalizing in the subsonic or ultrasonic ranges is a 0-point effect if it's all you can do, and costs points if you can vocalize in other ranges as well.

Combining Ultrasonic or Subsonic Speech with Mute (No Speech) represents the ability to vocalize sounds in your chosen frequency range, without the ability to use humanlike language.

Mundane Communication options: frequency range (normal; subsonic only; ultrasonic only); Voice; Mute (No Speech; No Voice); Stuttering; Mimicry; Penetrating Call; Disturbing Voice.

Exotic Communication

You're on a different wavelength. If you're aquatic and sentient, don't forget Speak Underwater (or take it free, at the GM's option). Speak With Animals/Fish/Plants are written with people in mind; if you are one of these creatures, assume you can speak with your kind for free (and add a Speak With Humans advantage if the GM requires).

Subsonic and Ultrasonic Speech here represent the ability to vocalize in these ranges in addition to the normal range. Communication via pheromones, color, or other extraordinary means is possible; invent as you like. Secret Communication covers exotic means of communication that can't even be detected by those not tuned in.

Exotic Communication options: none; Radio Speech; Broadcast; Speak Underwater; Speak With Animals; Speak With Fish; Speak With Plants; Subsonic Speech; Ultrasonic Speech; Secret Communication.

Artificial Enhancements

Organic Enhancements

Many GURPS or GULLIVER traits can be added to existing characters through the wonders of biotechnology. See Bio-Tech.

Mechanical Enhancements

The mechanical add-ons below are found in CI, with lots more in Cyberpunk, Ultra-Tech etc. Other traits could be used to build mechanical beings:

Mechanical Enhancement options: Interface Jack; Mechanical Telepathy; Neural Cyberdeck Interface; all other bionic and cyborg modifications.

Scaling Stats for Size

Multiply your base ST, base HP (not HT!), and base DR (if any) by your Linear Scale. The resulting ST is Combat ST, used for combat, damage, Contests of ST, etc. Pay for your final Combat ST with normal GURPS ST costs, pay for final DR normally, and pay for final HP with Extra/Reduced Hit Points.

Multiply your base ST by your Area Scale to get Load ST, used for all lifting, carrying, and encumbrance purposes. Purchase any points of Load ST that are above or below Combat ST at only half cost.

You can adjust Move, Reach, and sustenance requirements with existing GURPS rules: modify Reach through Extra Reach (separately for each limb!), modify Move through Reduced or Enhanced Move (separately for running, swimming and flying move!), and add Decreased or Increased Life Support.

Or use GULLIVER's Size trait to modify all these at once; it's a lot easier.

Finally, consider Inconvenient Size if you haven't added it already.

Intellectual and Personality Traits

Intellectual Performance

Traits related to attention and creativity are listed under Personality Traits, though they could be grouped here too.

General intellect options: IQ; Common Sense.

Mundane inborn talent options: Incompetence; Lightning Calculator; Intuitive Mathematician; Mathematical Ability; Innumerate; Language Talent; Musical Ability; Sensie Talent.

Esoteric inborn talent options: Danger Sense; Intuition; Autotrance; Chronolocation.

Memory and learning options: Eidetic Memory (first level; second level); Cannot Learn; Absent-Mindedness; Amnesia.

Symbolic processing options: Dyslexia; Non-Iconographic.

Miscellaneous flaw options: Flashbacks; Voices; Pre-Frontal Lobotomy.

Sentience options: Bestial; Mindshare; Presentient; Racial Memory.

Personality Traits

The below recap the Personality Traits listed in neater form on CI p. 180, with some individual additions and a couple more categories. The category Belligerence covers general aggressiveness, though "aggressive" is a term with broader meanings.

Chauvinism options: Strong Xenophilia; Xenophilia; Undiscriminating; Broad-Minded; human norm; Chauvinistic; Intolerance: Racial; Xenophobia.

Concentration options: Short Attention Span; Distractible; Lover's Distraction; human norm; Attentive; Single-Minded. Alertness and Absent-Mindedness work here too.

Curiosity options: Obdurate; Incurious; Staid; human norm; Nosy; Curious; Extremely Curious.

Egotism options: Slave Mentality; Hive Mentality; Low Self-Image; Selfless; Guilt Complex; Humble; human norm; Proud; Selfish; Self-Centered; Overconfident; Glory Hound.

Empathy options: Low Empathy; Solipsist; Callous; Oblivious; human norm; Responsive; Sensitive; Charitable; Empathy; Cultural Adaptability.

Exotic Empathy Options: none; Animal Empathy; Beast-Kin; Plant Empathy; Tree-Kin; Spirit Empathy.

Gregariousness options: Reclusive; Loner; Uncongenial; human norm; Congenial; Chummy; Gregarious.

Imagination and Flexibility options: Stubbornness; Hidebound; Dull; human norm; Dreamer; Imaginative; Versatile.

Suspicion options: Unfazeable; Imperturbable; Fearlessness; Collected; Cool; human norm; Careful; Edgy.

Industriousness options: Compulsive Behavior: Workaholic; human norm; Laziness.

Willpower options: Weak Will; human norm; Strong Will.

Patience options: Impulsiveness; human norm; patient (quirk).

Belligerence options: Bully; Bad Temper; human norm; Pacifism.

Avarice options: Greed; Miserliness; human norm; Charitable; Extravagance.

Addiction and Compulsion options: none; Gluttony; Lecherousness; VR Addiction; Alcoholism; Sadism; Trickster; Murder Addiction; Kleptomania; Megalomania; Pyromania; Obsession; Addiction; Compulsive Behavior; Trademark.

Personality Disorder options: none; Split Personality; Killjoy; Manic-Depressive; Chronic Depression; Lunacy; Nightmares; Phobia; Delusions; Jealousy;

Personal Belief options: none; Code of Honor; Fanaticism; Extreme Fanaticism; Honesty; Truthfulness; Vow; Higher Purpose; Pacifism; Disciplines of Faith; Sense of Duty.

Stress Reactions

Here's a new Non-Combat paralysis, or deer-in-headlights syndrome. Pick a stimulus that freezes you, such as bright lights at night, or loud noises. Make the usual check for stunning in its presence. For more fun, add one predetermined response to a failed roll – not something useful like "run away", but rather "yelp and freeze wide-eyed", "curl up in a ball", or "jump straight up" (an armadillo's first and last response to an approaching car). Use a base cost of -15 points for this Non-Combat Paralysis, reduced for frequency of the stimulus.

Any of the above reactions – or just plain freezing – in a combat situation is Combat Paralysis, worth its usual -15 points.

Stress Reactions options: none; Combat Reflexes; Combat Paralysis; Non-Combat Paralysis; Cowardice; Bad temper; Berserk; Bloodlust; Phobia; Fearlessness; Unfazeable; Indecisive; On the Edge; Post-Combat Shakes; Stress Atavism.

Skills and Learned Traits

These are traits that represent training or education, not physiological modifications. Some could be inborn instincts; others (like Iron Hand) come from training.

Skills and Learned Traits options: G-Experience; Gadgeteer; combat abilities (Enhanced Block; Enhanced Parry; Enhanced Block; Weapon Master; Trained By a Master; Sharpshooter; Style Familiarity; Iron Hand); literacy (Literacy; Semi-Literacy; Illiteracy); other skills (Racial Skill Bonus; Group Skill Bonus; Racially-Learned Skill).

Social Traits

If you're designing a race, consider its social structure. Solitary, pair-bonding, family groups/clans, packs/tribes, herds, hives... and then there are all the details of technology and culture you care to invent. Suggestions for those could fill a Book bigger than this one, so let's not even get started here.

Social Aptitude

Below are some of the traits that determine how well – or just how – you'll get along with others in society. The line between these and the personality traits above is purely arbitrary.

Stacking flaws

Personality and other social flaws, even the mundane, can produce funny results when they add up. For example, you can take several helpings of the Ignorance disadvantage if you're missing lots of society's required skills – and you'll find yourself hated more than murderers and vampires, according to the rules.

It's best to consider how poor a reaction all faults will get you – Ignorances, Odious Personal Habits, Bad Temper, No Sense of Humor, no driver's license, whatever – and keep the final disadvantage value in line with that.

The GM should also gear overall reactions to the worst trait you're displaying, and ignore or minimize the reaction penalties of lesser flaws. When you're looking at a -6 on reactions for a face that makes Cthulhu wince, does it really matter to horrified viewers that you have no sense of humor as well?

The Overlapping Disadvantage rule handles this well. Make groups of similar reaction traits and allow full points for the highest-value flaw in each group, and fewer points for the remainder. All reaction penalties usually won't be in effect at once anyway: a stammer or demonic voice doesn't matter if you're just standing quietly, bad looks don't matter on the phone, etc.

However you work it, what's important is to not be bound by the names below, blindly tallying up reaction penalties and point costs. Save the -6 or worse penalties for bloodsucking, undead leeches, not poorly-dressed, humorless nerds.

Social Aptitude options: Charisma; Odious Personal Habits; Shyness; Clueless; Easy to Read; Gullibility; No Sense of Humor; Fashion Sense; Pious; Rapier Wit; Ignorance; Sanctity; Lover's Distraction.

Social Status

This covers a lot of ground. Travel Restrictions is a new idea: use the same rules as Environmental Intolerance, except that "damage" takes the form of severe social or legal repercussions. Incarceration or exile might be worth quite a few points, parole or house arrest worth less.

Appearance, covered earlier, is also a social-related trait.

General status options: Status; Subjugated; Social Stigma; Uneducated; Travel Restrictions; Reputation.

Ally options: none; Allies; Ally Group; Patron; Contacts; Claim to Hospitality; Favor.

External demands options: none; Duty; Extremely Hazardous Duty; Reprogrammable Duty; Dependents; Enemies.

Identity options: normal; Alternate Identity; Mistaken Identity; Zeroed; Secret; Secret Identity; Evil Twin.

Wealth options: Dead Broke; Poor; Struggling; Average; Comfortable; Wealthy; Very Wealthy; Filthy Rich; Multimillionaire.

Background options: Mundane Background; Primitive; normal; Unusual Background; High Technology.

Religious status options: none; Clerical Investment; Clerical Rank; Excommunicated.

Military/police status options: none; Legal Enforcement Powers; Security Clearance; Military Rank; Police Rank.

Academic status options: none; Tenure; University Rank.

Other organizational status options: Administrative Rank; Merchant Rank etc.

Immunity options: none; Bardic Immunity; Diplomatic Immunity; Legal Immunity.

Family-related options: none; Heir; Disowned.

Supernormal Traits


GURPS offers numerous traits for weres, though its detailed rules have problems.


Whether part of a lycanthropic shapeshift or just a Towering Lad power, the below replaces GURPS' Growth and Shrinking traits. The cost calculations aren't terribly elegant; they're there until useful shapeshifting rules come along.

Variable Size (new)

5 points/level* + cost of traits

You can grow or shrink. Choose the Sizes you're able to hit: Size 0 through 6, Size -10 through -2, whatever. Pay normally for the largest of those Sizes, using the Size trait. Now pay an additional 5 points per Size level you can hit. You can also take Inconvenient Size, but based on your least inconvenient size.

Example: Your Super can cycle between Size -2 and Size +2. Pay normally for Size +2 [20], then 5 points each for the 5 Sizes you can attain [25]. Your least inconvenient size is Size 0, which in most games gets you no Inconvenient Size points at all.

Which of your Sizes is your "normal" one is a special effect, as is whether you revert to that size upon losing consciousness.

Changing Size takes one second per level of change. All normal Move, Reach, TH, and other effects of a new Size apply. But so far your stats, including weight, haven't changed at all! That's fine if the GM allows, although terribly unrealistic.

Changing stats: If you do want stats to change, figure your stats for each Size. You must pay for the best of everything: the best ST and HP you can achieve at large size, the best natural encumbrance at small size, etc. But you can take a Nuisance Effect limitation on the 5-point Variable Size cost for any Size level, equal to the value of all the great stuff you paid for but don't get at that level.

It turns out that the result of the above is almost always the maximum -80% limitation on the cost of Variable Size levels. So forget the calculations. If your weight and stats automatically scale with your size, just change the cost of Variable Size to 1 point/level (5, -80% = 1). Buy that, plus the Size cost of the largest Size you can attain, plus the cost of the best ST, HP, DR, negative encumbrance, and any other size-dependent traits you can attain. Add Inconvenient Size based on your least inconvenient size. You're done.

Damage: Damage taken "scales" with size change. If you lose 50% your HP at human size, you'll be at half HP when you shrink to mouse size. Lose another 25%, and you'll be at one-quarter HP whether you grow to human or giant size.

To build a permanently grown or shrunk character, just use normal Book 1 rules.

Shapeshifter options: Shapeshifter; Morph; Untrained Shape-Changing; Uncontrolled Change; Variable Size.


CI offers the following as superpowered traits, and Supers covers a whole additional range of powers. Growth and Shrinking have been removed and replaced with the above.

Superpower options: Absorption; Costume; Altered Time Rate; Broadcast; Compartmentalized Mind; Duplication; Enhanced Time Sense; Growth; Shrinking; Healing; Insubstantiality; Invisibility; Invisibility to Machines; Invulnerability; Matter Surfing; Move Through Ice; Multiple Forms; Reflection; Transference; Transformation.

Karmic Traits

It was preordained that you read this far:

Karmic Trait options: general luck (Unluckiness; Luck; Extraordinary Luck; Ridiculous Luck; Super Luck); special luck (Daredevil; Serendipity); blessings/curses (Cursed; Cursed (Divine Curse); Blessed); background (Unusual Background; Karmic Ties); other (Destiny; Harmony With the Tao; Ying-Yang Imbalance; Weirdness Magnet).

Magical and Psionic Traits

Just about any trait can be associated with magical or psionic power, but the following are specifically so:

Magical Trait options: Magical Aptitude; Magic Resistance; Mana Damper; Mana Enhancer; Clerical Magic; Divination Talent; Inherent Magic (Knacks); Natural Spellcasting; Magic Susceptibility.

Psionic Trait options: all psi powers; Psionic Resistance; Mindlink; Special Rapport; Supersensitive; Telepathic Addiction.

Undead Traits

Undead can incorporate any trait found so far, with the following tailored specifically for them. (Note that Vampiric Dependency is a genetic disorder, and not paranormal.)

Undead options: Lifebane; Bloodthirst; The Draining; Infectious Attack; No Body Heat; Unliving; No Natural Healing; Unhealing; No Reflection; No Shadow; Pallor; Vampiric Dominance; Vampiric Immortality; Vampiric Invulnerability; Vampiric Resurrection.

Other Paranormal Traits

These are perfect for supers, mages, psis, undead, or any weird PC:

Other Paranormal Trait options: Awareness; Being of Pure Thought; Channeling; Divine favor; Extra Life; Faerie Empathy; Illuminated; Faith Healing; Familiar; Fugue; Insubstantiality; Lunar Influence; Medium; Oracle; Power Investiture; Reawakened; Retrogression; Second Sight; Snatcher; Spirit Empathy; Temporal Inertia; Time-Jumper; True Faith; Visualization; World-Jumper; World Sight; Dominance; Penetrating Vision; Allergic Susceptibility; Dread; Frightens Animals; Jinxed; Unique; Weirdness Magnet.

Finishing Up

Whew. If you have any energy left at all after that, it's time for the fun part: fleshing out and equipping the character, adding a story and motivations... and actually playing the game!

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GULLIVER v5.3 (2004.04.12) | Copyright 2004 T.Bone | T.Bone's GURPS Diner