The universe is an endless expanse of adventuring potential. On its billions of worlds, physics create every possible permutation of geology, while life’s endless creativity gives rise to organisms both eerily familiar and defying imagination. Regardless of their design, all of these creatures struggle to survive and thrive in their native habitats, from icy seas and lush fungus jungles to the savage pyroclastic flows of tidally heated moons or the rusting hulks of ancient alien megastructures.
The following section contains rules to help you as GM adjudicate the game universe, including rules for the vastness of space, for various types of planets and the different terrains that may be found on them, and for environmental effects and hazards that may come into play in a variety of settings. Rules for settlements and structures both natural and artificial are presented at the end of the section.
- Astronomical Objects
- Aerial Terrain
- Aquatic Terrain
- Desert Terrain
- Forest Terrain
- Hill and Mountain Terrain
- Marsh Terrain
- Urban Terrain
- Stealth and Detection in Urban Terrain
- Environmental Rules
- Cold Dangers
- Falling and Gravity
- Falling into Water
- Falling Objects
- Extreme Gravity
- High Gravity
- Low Gravity
- Zero Gravity
- Heat Dangers
- Catching on Fire
- Lava Effects
- Area of Effect
- Curing Radiation Effects
- Radiation Sickness
- Sleep Deprivation
- Smoke Effects
- Starvation and Thirst
- Suffocation and Drowning
- Slow Suffocation
- Underwater Combat
- Attacks from Land
- Attacks Underwater
- Spellcasting Underwater
The immeasurable gulf of space is home to everything on the Material Plane, housing more stars and planets than could ever be recorded. During their careers, the player characters will undoubtedly need to venture into space. Traveling from one planet to another, exiting the atmosphere of a planetoid, or visiting an orbiting space station are all examples of common travel that require at least a brief time in space. Many hazards of space can be mitigated by wearing armor or a standard space suit, but sometimes unlucky spacefaring adventurers get caught without them!
“Cosmic rays” is a catchall term for various interStellar radiation effects. They use the same rules as radiation. Most habitable planets maintain atmospheres capable of repelling these emissions. Such protected planets allow, at most, a low amount of radiation in infrequent bursts. Planets devoid of a protective atmosphere are constantly assailed by radiation of medium to severe intensity.
The void of space is effectively empty of matter, and this vacuum is perhaps the greatest danger of outer space. A creature introduced to a vacuum immediately begins to suffocate (see Suffocation and Drowning) and takes 1d6 bludgeoning damage per round (no saving throw). Because a vacuum has no effective temperature, the void of outer space presents no dangers from cold temperatures. A creature retains its body heat for several hours in a vacuum. Sound doesn’t travel in a vacuum.
Decompression occurs when a creature suddenly transitions from a pressurized environment to a vacuum, such as by being flung out of an airlock or being inside a sealed structure that becomes heavily damaged. Such a creature takes 3d6 bludgeoning damage (no saving throw) in addition to any suffocation damage.
Most creatures travel the vacuum of space in a starship.
Most living beings begin their lives on floating astronomical objects. These planets, planetoids, and stars are the hub of much adventure and vary in complexity of design and makeup. A brief summary of the different types of astronomical objects is presented below, along with various rules associated with each.
Classification of Astronomical Objects
There exist several different types of astronomical objects. Summarized below are the most prominent types encountered during interStellar exploration.
An asteroid is a fractured chunk of matter, notable for being too small to be considered a proper planetoid. Asteroids commonly lack any sort of ecosystem and are often bereft of an atmosphere and breathable air. Many see asteroids as exploitable resources, given that they are often rich in minerals of varying rarity.
As their name suggests, gas giants are worlds composed entirely of gas—frequently elements such as hydrogen and helium. They lack any natural solid surfaces to walk on and so have no proper ground. Creatures unable to fly or without flight-capable equipment or magic tumble toward the dense core of the world at the falling speed of a standard-gravity planet. Such a fall often takes days, given the immense size of these worlds. Near the center of a gas giant, a creature is subject to extreme gravity. The heart of a gas giant acts in many ways like a star (see Star below), including destroying creatures that don’t have full immunity to fire.
Some planets exist outside of the typical description of a (mostly) spherical mass of gases or silicate rocks and metals. These irregular worlds come in a variety of shapes, many of which are still considered theoretical. Some worlds might be Artificially designed in the shape of a torus. Other worlds, like a planet in the form of a cube or a world that is entirely flat, exist as the result of cosmic abnormalities or the direct intervention of the divine.
Satellites are objects, such as moons, orbiting any other form of planetoid. “Satellite” is a classification that can be applied to other astronomical objects as well, as many asteroids and terrestrial worlds are also satellites. Unlike other types of astronomical objects, a satellite isn’t necessarily a natural object. Alien markers and space stations are but a few types of Artificial constructs that hang in the gravitational field of planets. Some planets have only a single moon, while others (such as gas giants) boast dozens of objects caught in their gravitational fields.
A star—sometimes multiple stars—typically rests at the heart of a planetary system. Stars are massive balls of incandescent plasma that blast their orbiting planetoids with heat. While there are various categorizations of stars, from blue dwarf stars to yellow hypergiants, all stars produce enough heat to pose similar hazards to most adventurers. The surface of a star is so hot that only full immunity to fire allows a creature to survive there. Any creatures or items not immune to fire are instantly and utterly consumed down to the molecular level—only spells such as miracle or wish can bring back such victims.
Solar Flares: Occasionally, stars let off bursts of intense energy, visible upon their surfaces as flares of roiling plasma. These disturbances have a deadly and immediate effect on things on or near the surfaces of such turbulent stars. The peripheral danger of these flares is the devastating effect they have on unshielded electronic equipment and radio communications. These distortions can be felt millions of miles away from the star, and typically they cause various electronics and radio communications to cease functioning for 6d6×10 minutes.
An atmosphere is a layer of gases held in place by the pull of a planetoid’s gravity. The gravity and temperature of a planetoid impact its ability to retain an atmosphere. Most planets and planetoids support some manner of atmosphere. In addition to hospitable atmospheres, there are various other types of atmosphere that serve as hazards to most life.
As the name suggests, a corrosive atmosphere eats away at matter. The type and speed of the erosion varies, but the most common use of this term describes atmospheres capable of dissolving most matter. A typical corrosive atmosphere deals anywhere from 1 acid damage per minute up to 10d6 acid damage per round to creatures and objects within. Certain metals and treated materials may be immune to the specific atmosphere of a planet, and often the corrosion can be mitigated with dutiful preparation.
A creature on a planet without an atmosphere (or with an atmosphere so thin that it is effectively airless) is exposed to a vacuum.
A normal atmosphere is one that can support the majority of breathing life-forms. Most such atmospheres are composed of some combination of oxygen, nitrogen, and other nontoxic gases.
Most people use the word “planet” to refer to a terrestrial world. The ones closest to the star of a Solar system are the worlds most likely to be naturally habitable. They’re home to varying ecosystems, from barren, rocky landscapes to vibrant jungles of lush plant life and rushing waterways. Such worlds are sometimes categorized by their predominant features, leading to titles such as desert world, ice world, jungle world, and lava world.
A nonacclimated creature operating in a thick atmosphere treats it as somewhat harmful, due to the extra chemical compounds in the air and the increased atmospheric pressure. Every hour, such a creature must succeed at a Fortitude save (DC = 15 + 1 per previous check) or become sickened. This condition ends when the creature returns to a normal atmosphere. Conversely, the increased weight of the air grants a +4 circumstance bonus to Acrobatics checks to fly or Piloting checks to keep an aircraft in flight.
Severely thick atmospheres are far more dangerous. Every minute, a creature in such an atmosphere must succeed at a Fortitude save (DC = 15 + 1 per previous check) or begin to suffocate (see Suffocation and Drowning) as its lungs cease coping with the density of the oxygen inhaled and lose the strength to keep pumping air into its bloodstream.
Thinner atmospheres tend to cause a nonacclimated creature to have Difficulty breathing and become extremely tired. A typical thin atmosphere requires such a creature to succeed at a Fortitude save each hour (DC = 15 +1 per previous check) or become fatigued. The fatigue ends when the creature returns to a normal atmosphere.
Severely thin atmospheres can cause long-term oxygen deprivation to those affected in addition to the effects of a standard thin atmosphere. The first time a creature in a severely thin atmosphere fails its Fortitude save, it must succeed at a DC 25 Fortitude save or take 1 damage to all ability scores. A creature acclimated to high altitude (see Hill and Mountain Terrain) gains a +4 insight bonus to its saving throw to resist this effect.
Toxic atmospheres are composed of poisonous compounds and vary radically in their consistencies. Some toxic atmospheres are capable of sustaining oxygen-breathing life-forms, while others immediately suffocate those within them. Regardless of whether or not they allow creatures to breathe, toxic atmospheres are threats to most living creatures, as they act as an inhaled poison. Though the specific type of poison varies, many toxic atmospheres act as existing poisons but with radically different onset times and save DCs. Low-level toxic atmospheres can have onset times measured in hours or days, while heavily toxic atmospheres have onset times measured in rounds.
The following section includes information on a variety of biomes found on planets. Some planets could be entirely made up of a single biome, such as desert or forest worlds, while other planets contain a mix of the following terrain types.
On worlds where the atmosphere expands high above the physical boundaries of the surface, there exists a region of open air. Similarly, gas giants are made up of nothing more than a vast atmosphere, held in place by a starlike core. The most common rules sections to reference when using aerial terrain are Falling, Gravity, Suffocation and Drowning, and Weather. The rules for flying with the Acrobatics skill are also critical for many creatures operating in an aerial environment.
Most clouds are little more than condensed gas that obfuscates vision. Treat a cloud in an aerial environment using the same rules as fog cloud, except it’s a nonmagical effect. Other types of cloud exist, such as corrosive or toxic clouds, which operate in the same manner as those types of atmospheres (see above).
Stealth and Detection in Aerial Terrain
How far a character can see in the air depends on the presence or absence of clouds. Creatures can usually see 5d8×100 feet if the sky is completely clear, with minimal clouds (or other aerial objects) blocking their views. Clouds generally provide enough concealment to hide within (though the hiding creature might have Difficulty seeing out from its hiding place).
Aquatic terrain can be one of the least hospitable to PCs because most can’t breathe underwater. The ocean floor holds many marvels, including undersea analogues of any of the other terrain elements described in this section, but if characters find themselves in the water because they were bull-rushed off the back of a transport ship, the kelp beds or volcanic vents hundreds of feet below them don’t matter. The most common rules sections to reference when using aquatic terrain are Suffocation and Drowning and Underwater Combat. The rules for swimming with the Athletics skill are also critical for many creatures operating in an aquatic environment.
Lakes and oceans simply require a swim speed or successful Athletics checks to move through (typically, DC 10 in calm water, DC 15 in rough water, DC 20 in stormy water, and DC 30 in maelstrom water). Characters need a way to breathe if they’re underwater; lacking that, they risk drowning. When underwater, characters can move in any direction, including up and down.
At certain depths, the pressure of the surrounding water becomes so great that characters might be affected as if they were in a thick or severely thick atmosphere, even if they can breathe underwater.
Stealth and Detection Underwater
How far a character can see underwater depends on the water’s clarity. As a guideline, creatures can see 4d8×100 feet if the water is clear and 1d8×10 feet in murky water. Running water is always murky, unless it’s in a particularly large, slow-moving river. It is hard to find cover or concealment to hide underwater (except along the sea floor).
Desert terrain exists in cold, temperate, and warm climates, but all deserts share one common trait: very little precipitation. The three categories of desert terrain are tundra (cold desert), rocky deserts (often temperate), and sandy deserts (often warm). The most common rules sections to reference for adventures in these areas are Cold Dangers, Heat Dangers, Starvation and Thirst, and Weather.
Stealth and Detection in the Desert
In general, the maximum distance in desert terrain at which a creature can succeed at a Perception check to detect the presence of others is 6d6×20 feet; beyond this distance, elevation changes and heat distortion in warm deserts makes sight-based Perception checks impossible. The presence of dunes in sandy deserts limits spotting distance to 6d6×10 feet. The scarcity of undergrowth or other elements that offer concealment or cover makes using Stealth more difficult.
A forest can be composed of more than trees. On some worlds, vast fungal growths tower into the sky, while on others metallic veins rise from the ground and connect in spidery canopies. Common rules sections to reference for forests are Catching on Fire, Falling Objects, Smoke Effects, and Vision and Light.
Most forests are filled with trees, or something akin to trees, which provide partial cover to those standing in the same square as a tree. An average tree has an AC of 4, a hardness of 5, and 150 HP (see rules on smashing an object). A successful DC 15 Athletics check is enough to climb most trees.
Fungal blooms, vines, roots, and short bushes cover much of the ground in a forest. Undergrowth counts as difficult terrain, provides concealment (20% miss chance), and increases the DCs of Acrobatics and Stealth checks by 2. Squares with undergrowth are often clustered together. Undergrowth and trees aren’t mutually exclusive; it’s common for a 5-foot square to have both a tree and undergrowth.
Stealth and Detection in a Forest
In a sparse forest, the maximum distance at which a creature can succeed at a Perception check to detect the presence of others is 3d6×10 feet. In a medium forest, this distance is 2d8×10 feet, and in a dense forest it is 2d6×10 feet.
The background noise of a forest makes Perception checks that rely on sound more difficult, increasing the DC of the check by 2 (not 1) per 10 feet.
Hill and Mountain Terrain
Hill terrain describes rises in the immediate area, often multiple hills spread over miles. This type of terrain can occur in any other biome. Mountains are steeply rising rock, metal, or even the organic crust of the planet. The most common rules sections to reference when using hill and mountain terrain are Cold Dangers, Falling, and Weather.
Usually formed by natural geological processes, chasms are common dangers in mountainous areas. Chasms aren’t hidden, so characters won’t (usually) fall into them by accident. A typical chasm is 2d4×10 feet deep, at least 20 feet long, and anywhere from 5 to 20 feet wide. It usually requires a successful DC 15 Athletics check to climb the wall of a chasm. In mountain terrain, chasms are typically 2d8×10 feet deep.
A vertical plane of stone, a rock wall requires one or more successful DC 25 Athletics checks to ascend. A typical rock wall is from 2d4×10 feet tall to 2d8×10 feet tall.
At particularly high altitudes, the thinning atmosphere poses a challenge for many creatures, with the same effects as a thin atmosphere. A creature residing at a high altitude for 1 month becomes acclimated and no longer takes these penalties, but it loses this benefit if it spends more than 2 months away from high-altitude terrain and must reacclimatize upon returning.
Stealth and Detection in Hills and Mountains
As a guideline, the maximum distance in mountain terrain at which a creature can succeed at a Perception check to detect the presence of others is 4d10×10 feet. In hill terrain, the maximum distance is 2d10×10 feet. It’s easier to hear distant sounds in the mountains. The DCs of Perception checks that rely on sound increase by 1 per 20 feet between listener and source, not 1 per 10 feet.
Two categories of marsh exist: relatively dry moors and watery swamps. Both are often bordered by lakes, which are effectively a third category of terrain found in marshes. The most common rules sections to reference for marshes and swamps are Suffocation and Drowning, Underwater Combat, and Weather (see below).
If a square is part of a shallow bog, it has deep mud or standing water of about 1 foot in depth. It counts as difficult terrain, and the DCs of Acrobatics checks attempted in such a square increase by 2.
A square that is part of a deep bog has roughly 4 feet of standing water. It counts as difficult terrain, and Medium or larger creatures must spend 4 squares of movement to move into a square with a deep bog, or characters can swim if they wish. Small or smaller creatures must swim to move through a deep bog. Tumbling is impossible in a deep bog.
The water in a deep bog provides cover for Medium or larger creatures. Smaller creatures gain improved cover. Medium or larger creatures can crouch as a move action to gain this improved cover. A creature with this improved cover takes a –10 penalty to attacks against creatures that aren’t underwater.
Deep bog squares are usually clustered together and surrounded by an irregular ring of shallow bog squares.
Stealth and Detection in a Marsh
In a moor, the maximum distance at which a creature can succeed at a Perception check to detect the presence of others is 6d6×10 feet. In a swamp, this distance is 2d8×10 feet. Vegetation and deep bogs provide plentiful concealment (20% miss chance), so it is possible to use Stealth to hide in a marsh.
Urban terrain can be found in most settlements where the people have greatly exerted their influence over the surrounding environment, constructing buildings where they can live and work in comfort and laying well-defined roads, usually paved. This type of terrain can occur in just about any biome, and it often supersedes the environmental effects of that biome. Urban terrain can include space stations, and it is often replete with technology. The most common rules sections to reference when using urban terrain are settlements, structures, and vehicles, as well as Breaking Objects and sometimes Radiation.
Stealth and Detection in Urban Terrain
In a settlement with wide, open streets, the maximum distance at which a creature can succeed at a Perception check to detect the presence of others is 2d6×10 feet. In a settlement where the buildings are more crowded, standing close together, this distance is 1d6×10 feet. The presence of crowds might reduce this distance.
Thanks to twisting side streets and vehicles that can provide cover, it’s usually easy for a creature to use Stealth to hide in a settlement. In addition, settlements are often noisy, making Perception checks that rely on sound more difficult; this increases the DC of any such checks by 2 per 10 feet.
Weather can play an important role in an adventure. The following section describes weather common on most habitable worlds. Additional rules for cold and heat dangers can be found in Environmental Rules.
Rain and Snow
Bad weather frequently slows or halts travel and makes it virtually impossible to navigate from one spot to another. Torrential downpours and blizzards obscure vision as effectively as dense fog. Most precipitation is rain, but in cold conditions it can manifest as snow, sleet, or hail. If the temperature drops from above freezing to 32° F or below, it might produce ice.
Heavy snow has the same effects as normal snowfall but also restricts visibility as fog does (see Fog below). A day of heavy snow leaves 1d4 feet of snow on the ground. Snow at this depth counts as difficult terrain, and it costs 4 squares of movement to enter a square covered with heavy snow. Heavy snow accompanied by strong or severe winds might result in snowdrifts 1d4×5 feet deep, especially in and around objects big enough to deflect the wind—a reinforced wall or a large force field, for instance. There’s a 10% chance that a heavy snowfall is accompanied by lightning (see Thunderstorm).
There are other forms of precipitation, such as freezing rain, hail, and sleet. These generally function as rain when falling, but at the GM’s discretion, they may also have effects on movement similar to snow once they accumulate on the ground.
The combined effects of precipitation (or dust) and wind that accompany storms reduce visibility ranges by three-quarters, imposing a –8 penalty to Perception checks. Storms make aiming with ranged weapons difficult, imposing a –2 penalty to attack rolls, and archaic ranged weapons can’t be fired at all. Storms automatically extinguish unprotected flames. Storms commonly appear in three types: dust, snow, or thunder.
These desert storms differ from other storms in that they have no precipitation. Instead, a dust storm blows fine grains of sand that obscure vision, smother unprotected flames, and can even choke protected flames (50% chance). Most dust storms are accompanied by severe winds and leave behind a deposit of 1d6 inches of sand. There is a 10% chance for a dust storm to be accompanied by windstorm-magnitude winds (see Table 11–6: Wind Effects); this greater dust storm deals 1d3 nonlethal damage each round to anyone caught out in the open without shelter and also poses a choking hazard (see Suffocation and Drowning). A greater dust storm leaves 2d3–1 feet of fine sand in its wake.
In addition to the wind and precipitation common to other types of storms, a snowstorm leaves 1d6 inches of snow on the ground afterward.
In addition to wind and precipitation, a thunderstorm is accompanied by lightning that can pose a hazard to characters who don’t have proper shelter (especially those in metal armor). As a rule of thumb, assume one bolt per minute for a 1-hour period at the center of the storm (GM rolls to hit). Each bolt deals between 4d8 and 10d8 electricity damage. One in 10 thunderstorms is accompanied by a tornado.
Very high winds and torrential precipitation reduce visibility to zero, making Perception checks and all ranged weapon attacks impossible. Powerful storms are divided into the following types.
Blizzard: The combination of high winds, heavy snow (typically 1d4 feet), and extreme cold make blizzards deadly for those unprepared for them.
Hurricane: In addition to very high winds and heavy rain, hurricanes are accompanied by floods. Most adventuring activity is extremely difficult under such conditions.
Tornado: With incredibly high winds, tornadoes can severely injure and kill creatures pulled into their funnels.
Windstorm: While accompanied by little or no precipitation, windstorms can cause considerable damage simply through the force of their winds (see Winds below).
Wind can create a stinging spray of dust, sand, or water, fan a large fire, rock an atmospheric transport midflight, and blow gases or vapors away. If powerful enough, it can even interfere with some ranged attacks and knock characters down. Below are the most common wind forces seen on habitable worlds.
A gentle breeze, having little or no game effect.
A steady wind often extinguishing small, unprotected flames.
Gusts that automatically put out any unprotected flames. Such gusts impose a –2 penalty to nonenergy ranged weapon attack rolls.
Nonenergy ranged weapon attack rolls take a –4 penalty.
Powerful enough to bring down branches, if not whole trees. Nonenergy ranged weapon attack rolls take a –4 penalty, while attacks with archaic ranged weapons are impossible. Perception checks that rely on sound take a –8 penalty due to the howling of the wind. Small characters might be knocked down.
Nonenergy ranged weapon attack rolls take a –8 penalty, and archaic ranged weapon attacks are impossible. Perception checks based on sound are impossible: all characters can hear is the roaring of the wind. Hurricane-force winds often fell trees. Most characters are knocked down due to the force of these winds.
All flames are extinguished. All nonenergy ranged weapon attacks are impossible, as are sound-based Perception checks. A creature in close proximity to a tornado that fails a DC 15 Strength check is sucked toward the tornado. All creatures that come into contact with the actual funnel cloud are picked up and whirled around for 1d10 rounds, taking 6d6 bludgeoning damage per round, before being violently expelled in a random direction (falling damage, described below, might apply). While a tornado’s rotational speed can be as great as 300 mph, the funnel itself moves forward at an average of 30 mph (roughly 250 feet per round). A tornado uproots trees, destroys buildings, and causes similar forms of major destruction.
|Wind Force||Wind Speed||Ranged Attack Penalty*|
* This applies only to nonenergy ranged weapons. Larger weapons, such as starship weapons, ignore this penalty.
The following is a compilation of rules appropriate for use in a variety of environments.
Cold and exposure deal nonlethal damage to the victim. A character can’t recover from the damage dealt by a cold environment until she gets out of the cold and warms up again.
An unprotected character in cold weather (below 40° F) must succeed at a Fortitude save each hour (DC = 15 + 1 per previous check) or take 1d6 nonlethal cold damage. A character can attempt Survival skill checks to gain a bonus to this saving throw and might be able to apply this bonus to other characters as well.
In conditions of severe cold (below 0° F), an unprotected character must succeed at a Fortitude save every 10 minutes (DC = 15 + 1 per previous check) or take 1d6 nonlethal cold damage. A character can attempt Survival skill checks to gain a bonus to this saving throw and might be able to apply this bonus to other characters as well.
Extreme cold (below –20° F) deals 1d6 lethal cold damage per minute (no saving throw). In addition, a character must succeed at a Fortitude save (DC = 15 + 1 per previous check) each minute or take 1d4 nonlethal cold damage. Colder environments can deal more damage at the GM’s discretion.
A character who takes any damage from cold or exposure is beset by frostbite or hypothermia (same as fatigued). These penalties end when the character recovers the nonlethal damage she took from the cold and exposure.
Ice Icy surfaces count as difficult terrain, and the DCs for Acrobatics checks attempted on ice increase by 5. Characters in prolonged contact with ice might run the risk of taking damage from severe cold.
A character that falls takes 1d6 damage per 10 feet fallen, to a maximum of 20d6. A character that takes damage from a fall lands prone.
If a character deliberately jumps instead of merely slipping or falling, the damage is the same but the first 1d6 is nonlethal damage. On a successful DC 15 Acrobatics check, the character avoids taking damage from the first 10 feet fallen and converts the damage from the second 10 feet to nonlethal damage. For example, a character who slips from a ledge 30 feet up takes 3d6 damage. If the same character deliberately jumps, he takes 1d6 nonlethal damage and 2d6 lethal damage. and if the character leaps down with a successful DC 15 Acrobatics check, he takes only 1d6 nonlethal damage and 1d6 lethal damage from the plunge.
The damage from the first 10 feet of a fall onto a yielding surface (such as soft ground or mud) is converted into nonlethal damage. This conversion is cumulative with damage reduced through deliberate jumps and successful Acrobatics checks.
A character can’t cast a spell or activate an item while free-falling unless the fall is greater than 500 feet or the spell or item can be used as a reaction. Casting teleport or a similar spell while falling doesn’t end the character’s momentum; it just changes her location, meaning that she still takes falling damage, even if she arrives atop a solid surface.
Falling and Gravity
The rules for falling presented here assume standard gravity. For planets with high or low gravity, double or halve the damage amounts, respectively. Falling in extreme gravity deals as least triple the listed damage, and potentially even more.
Falling into Water
Falls into water are handled somewhat differently. If the water is at least 10 feet deep, a falling character takes no damage for the first 20 feet fallen and 1d3 nonlethal damage per 10-foot increment for the next 20 feet fallen. Beyond that, falling damage is lethal damage as normal (1d6 per additional 10-foot increment).
A character who deliberately dives into water takes no damage with a successful DC 15 Athletics check or DC 15 Acrobatics check, as long as the water is at least 10 feet deep for every 30 feet fallen. The DC of the check increases by 5 for every 50 feet of the dive.
Just as characters take damage when they fall more than 10 feet, so too do they take damage when they are hit by falling objects.
An object that falls upon a character deals damage based on its size and the distance it fell. Table 11–7: Damage from Falling Objects determines the amount of damage dealt by an object based on its size. Note that this assumes the object is made of dense, heavy material, such as metal or stone. Objects made of lighter materials might deal as little as half the listed damage, subject to the GM’s discretion. For example, a Huge boulder that hits a character deals 6d6 bludgeoning damage, whereas a Huge wooden wagon might deal 3d6 bludgeoning damage. In addition, if an object falls less than 30 feet, it deals half the listed damage. If an object falls more than 150 feet, it deals double the listed damage. Note that a falling object takes the same amount of damage as it deals.
Dropping an object on a creature requires a ranged attack against its KAC. Such attacks generally have a range increment of 20 feet. If an object falls on a character (instead of being thrown), that character can attempt a DC 15 Reflex save to take half damage if he is aware of the object. Falling objects that are part of a trap use the trap rules instead of these general guidelines.
|Tiny or smaller||1d6|
Gravitational differences between planets have the potential to cripple characters or make them superheroes—and sometimes both at the same time. Most planets habitable by humanoids have a gravity level defined as standard, which makes them similar enough that trying to arbitrate the difference isn’t necessary. Others, however, require special consideration. For planets with gravities that aren’t quite standard but don’t fall into the exact categories below, the GM might decide to assume the effects are proportional. For example, a planet with half standard gravity allows player characters to jump twice as high, whereas one with 1-1/2 standard gravity cuts jump heights by a third. In all cases, these effects last until the PCs adjust to the gravity (a process that typically takes about a month of living under such conditions). See Flying for information about flying on planets with high or low gravity.
A planet where the gravity is at least five times as strong as standard gravity is extremely dangerous to most creatures. In addition to the limitations of high gravity (see below), a creature in this environment takes an amount of nonlethal bludgeoning damage per round (at least 1d6, but potentially more, depending on the intensity of the gravity). Once a character takes sufficient nonlethal damage to be reduced to 0 Hit Points, any further damage from extreme gravity is lethal bludgeoning damage.
On high-gravity worlds, characters are burdened by their increased weight, and their physical abilities are affected accordingly. On a high-gravity world, where the gravity is at least twice as strong as standard gravity, a character (and her gear) weighs twice as much as on a standard-gravity world, but she has the same amount of strength. Such characters move at half speed, can jump only half as high or as far, and can lift only half as much. Thrown weapons (though not those of natives) have their ranges cut in half as they fall to the ground more rapidly. Modifications to running, jumping, and lifting can be negated by certain magic or technology, but projectiles remain affected. Characters who remain in a high-gravity environment for long periods (more than a day) often become fatigued and remain so until they leave the planet or become accustomed to the gravity.
Low-gravity worlds are liberating to most species acclimated to standard-gravity worlds. Such characters’ muscles are far more effective than normal. On a low-gravity world, where the gravity is no greater than a third of standard gravity, PCs can jump three times as high and as far and lift three times as much. (Movement speed, however, stays the same, as moving in great bounds is awkward and difficult to control.) Thrown weapons have their range categories tripled.
Standard-gravity worlds have gravity approximately the same as Earth’s gravity.
Movement in zero gravity (also referred to as zero-g) is not the same as flight. Controlled movement is difficult without some form of propulsion, and creatures without something to push off from often find themselves floating aimlessly. A creature in a zero-gravity environment can’t take move actions to move its speed, crawl, or take a guarded step. If a creature is adjacent to or in the same square as an object (including a wall, floor, or ceiling) or another creature one size category smaller than itself or larger, it can take a move action to push off that object or creature, moving at half its land speed in a direction of its choosing (as appropriate); if that object or creature is movable, it begins moving in the opposite direction at that same speed.
Moving in Zero-G: A creature that moves in a given direction continues to move in that direction at the same speed at the beginning of its turn each round (without taking any action); it must move the full distance unless it is able to change its motion by latching on to an object or creature, pushing off in a new direction, or creating thrust of some kind (all of which are considered move actions). If a creature runs into a solid object during its movement, it must succeed at a DC 20 Acrobatics or Athletics check to safely stop its movement; failure means that creature gains the off-kilter condition. If a creature runs into another creature during its movement, both creatures must each attempt a DC 20 Acrobatics or Athletics check to avoid gaining the off-kilter condition. A creature anchored to a solid object (such as by the boot clamps available with most armor) receives a +4 bonus to this check. An off-kilter creature in a zero-gravity environment can steady itself as a move action that requires a surface to grab on to or some method of propulsion; alternatively, that creature can throw a single item weighing at least 4 bulk (for Medium creatures; 2 bulk for Small creatures) to reorient itself and remove the off-kilter condition.
If provided with sufficient handholds, a creature with a climb speed can move along a wall at full speed, as can any creature that succeeds at a DC 20 Acrobatics or Athletics check. Creatures that fly via methods that require an atmosphere, such as wings or turbofans, can’t use their fly speeds in a vacuum; once they reenter an atmosphere, they can recover and get their bearings within 1d4 rounds, after which they can fly normally. Magical flight and methods of flight that provide their own thrust, such as maneuvering jets, are not affected. A character in a zero-gravity environment can lift and carry 10 times her normal amount.
Weapons: Thrown weapons have their range increments multiplied by 10 in zero-g. In addition, all ranged weapons no longer have a maximum number of range increments—their wielders simply continue to accrue penalties the farther away the target is.
Heat deals nonlethal damage to the victim. A character can’t recover from the damage dealt by a hot environment until she gets out of the heat and cools off.
A character in very hot conditions (above 90° F) must attempt a Fortitude saving throw each hour (DC = 15 + 1 per previous check) or take 1d4 nonlethal fire damage. Characters wearing heavy clothing or armor of any sort take a –4 penalty to their saving throws. A character can attempt a Survival check to receive a bonus to this saving throw, and might be able to apply this bonus to other characters as well.
In severe heat (above 110° F), a character must attempt a Fortitude saving throw once every 10 minutes (DC = 15 + 1 per previous check) or take 1d4 nonlethal fire damage. Characters wearing heavy clothing or armor of any sort take a –4 penalty to their saves. A character can attempt a Survival check to receive a bonus to this saving throw and might be able to apply this bonus to other characters as well.
Extreme heat (air temperature over 140° F, boiling water, fire, and lava) deals lethal fire damage. Breathing air in extreme heat deals 1d6 fire damage per minute (no saving throw). In addition, a character must attempt a Fortitude saving throw every 5 minutes (DC = 15 + 1 per previous check) or take 1d4 nonlethal fire damage. Hotter environments can deal more damage at the GM’s discretion.
A character who takes any damage from heat exposure suffers from heatstroke (same as the fatigued condition). These penalties end when the character recovers from the nonlethal damage she took from the heat.
Boiling water deals anywhere from 1d6 to 10d6 fire damage per round of exposure, depending on water temperature and level of immersion.
Catching on Fire
Characters exposed to burning oil, bonfires, and noninstantaneous magical fires might find their clothes, hair, or equipment on fire. Spells or technological items with an instantaneous effect don’t normally set a character on fire, since the heat and flame from these come and go in a flash.
A character at risk of catching fire must succeed at a Reflex saving throw (usually DC 15) or gain the burning condition. Those whose clothes or equipment catch fire must attempt a separate Reflex saving throw (at the same DC) for each item. On a failed saving throw, flammable items take the same amount of damage as the character.
Lava or magma deals a minimum of 2d6 fire damage per round of exposure, while cases of total immersion (such as when a character falls into the crater of an active volcano) deal upward of 20d6 fire damage per round. The exact damage is left to the GM’s discretion, based on situational terrain elements.
Damage from lava continues for 1d3 rounds after exposure ceases, but this additional damage is only half of that dealt during actual contact (that is, 1d6 or 10d6 per round). Immunity or resistance to fire serves as an immunity or resistance to lava or magma. A creature immune or resistant to fire might still drown if completely immersed in lava (see Suffocation and Drowning).
Radiation is a very real threat to adventurers, whether it’s the radiation emitted from stars or the radiation generated by various technological wonders of the universe. Radiation is a poison effect that weakens an affected creature’s Constitution and can also inflict an affected creature with a disease called radiation sickness. Radiation dangers are organized into four categories: low, medium, high, and severe. The effects of these categories of radiation are described on Table 11–8: Radiation Levels.
Area of Effect
Radiation is an emanation poison, meaning that a victim only needs to enter an area suffused with radiation to be affected by it. Radiation suffuses a spherical area of effect that can extend into solid objects. The closer one gets to the center of an area of radiation, the stronger the radiation effect becomes. Radiation entries list the maximum level of radiation in an area, as well as the radius out to which this radiation level applies. The radiation continues to suffuse each increment out to an equal length beyond that radius, its strength degraded by one level per increment. For example, a spherical area of high radiation with a radius of 20 feet creates a zone of medium radiation spanning 20 feet to 40 feet from the center in all directions, and a similar zone of low radiation spanning 40 to 60 feet from the center.
Curing Radiation Effects
A creature that leaves an area suffused with radiation is essentially cured of the poison effect. Ending the source of radiation or successfully casting remove radioactivity has the same effect. As usual for poison effects, an affected creature requires rest to recover from radiation poisoning. Remove affliction doesn’t cure a creature of the effects of radiation poisoning, but remove radioactivity does.
If a creature has been exposed to enough radiation, it might contract radiation sickness, which acts like a noncontagious disease. Symptoms of radiation sickness include nausea, vomiting, and loss of hair. Radiation sickness can be treated like any disease, although it can’t be cured with remove affliction. Remove radioactivity can cure radiation sickness.
Type poison, emanation (see above); Save Fortitude (see chart)
Track Constitution; Frequency 1/round
Effect At each state of impaired and beyond, the victim must succeed at a DC 18 Fortitude saving throw or contract the radiation sickness disease (see below).
Type disease; Save Fortitude (same DC as the level of radiation that caused the radiation sickness)
Track physical; Frequency 1/day
Effect Radiation sickness isn’t contagious.
Cure 3 consecutive saves
|Radiation Level||Fort DC|
A character who needs to sleep must get at least 6 hours of sleep every night. If she doesn’t, she must attempt a Fortitude save (DC = 15 + 1 per previous check) after each night she doesn’t sleep enough. The first failed check causes her to become fatigued and take a –1 penalty to saving throws against effects that cause the asleep condition. A second failed check causes her to become exhausted, and the penalty to saving throws against effects that cause the asleep condition increases to –2.
A character who inhales heavy smoke must attempt a Fortitude save each round she’s within the smoke (DC = 15 + 1 per previous check) or spend that round choking and coughing. A character who chokes for 2 consecutive rounds takes 1d6 nonlethal damage. Smoke obscures vision, giving concealment (20% miss chance) to characters within it.
Starvation and Thirst
Characters might find themselves without food or water and with no means to obtain them. In normal climates, Medium characters need at least a gallon of fluids per day to avoid thirst and about a pound of decent food per day to avoid starvation; Small characters need half as much. In very hot climates, characters need two or three times as much water to avoid thirst.
A character can go without water for 1 day plus a number of hours equal to his Constitution score. After this time, the character must succeed at a Constitution check each hour (DC = 10 + 1 per previous check) or take 1d6 nonlethal damage.
A character can go without eating food for 3 days. After this time, the character must succeed at a Constitution check (DC = 10 + 1 per previous check) each day or take 1d6 nonlethal damage.
A character who has taken any damage from lack of food or water is fatigued. Damage from thirst or starvation cannot be recovered until the character gets food or water, as needed—not even magic that restores Hit Points heals this damage.
Suffocation and Drowning
A character who has no air to breathe can hold her breath for a number of rounds equal to twice her Constitution score. If a character takes a standard or full action, the remaining duration that the character can hold her breath is reduced by 1 round. After these rounds have elapsed, the character must attempt a Constitution check (DC = 10 + 1 per previous check) each round in order to continue holding her breath.
When the character fails one of these Constitution checks, she begins to suffocate. In the first round, she is reduced to 0 Hit Points and is unconscious and stable. In the following round, she is no longer stable and begins dying. In the third round, she suffocates and dies.
An unconscious character must begin attempting Constitution checks immediately upon losing air supply (or upon becoming unconscious, if the character was conscious when her air was cut off). Once she fails one of these checks, she immediately drops to 0 Hit Points and is dying. On the following round, she suffocates and dies.
A Medium creature can breathe easily for 6 hours in a sealed cubic chamber measuring 10 feet on a side. After that time, the creature takes 1d6 nonlethal damage every 15 minutes.
Each additional Medium creature or significant fire source (a torch, for example) proportionally reduces the time the air will last (two Medium creatures will run out of air in 3 hours, and so on). Small characters consume half as much air as Medium characters. A creature stuck in a starship or space station whose life support systems have completely failed will run out of breathable air in a similar fashion; while these structures are often larger than a 10-foot cube, they are also often occupied by several creatures. On average, a crew of four in a Medium starship without a source of fresh air can breathe easily for 20 hours.
Land-based creatures usually have considerable Difficulty when fighting in water, as it affects a creature’s attack rolls, damage, and movement. The following adjustments apply whenever a character is swimming, walking in chest-deep water, or walking along the bottom of a body of water.
Attacks from Land
Characters swimming or floating in water that is at least chest deep and characters who are fully immersed have cover against attacks made from the surface.
Most attacks made underwater take a –2 penalty and deal half damage. Attacks that deal fire damage do only one-quarter damage. Attacks that deal electricity damage take a –4 penalty rather than a –2 penalty. Melee attacks that deal piercing damage deal full damage. Thrown weapons are ineffective underwater, even when launched from land.
A creature that is attempting Constitution checks to hold its breath can’t concentrate enough to cast spells. Some spells might work differently underwater, subject to the GM’s discretion.