Environmental Rules
Starfinder Core Rulebook, page 400
The following is a compilation of rules appropriate for use in a variety of environments.
Cold Dangers
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 (see page 148).
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.
Sleep Deprivation
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 (see page 273). 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.
Smoke Effects
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.
Underwater Combat
Land-based creatures usually have considerable difficulty when fighting in water, as it affects a creature’s attack rolls, damage, and movement (see page 137 for more on swimming). 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.
Attacks Underwater
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.
Spellcasting Underwater
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.
In this section
- Falling 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.
- Gravity Gravitational differences between planets have the potential to cripple characters or make them superheroes—and sometimes both at the same time.
- Heat Dangers 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.
- Radiation 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.
- 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.
