Inner Fire (3.5e Creature Ability)

Inner Fire
Summary::Level 3 ability of the Lava Dragon sphere

All lava dragons have some capability to contain a small amount of their fiery homes and take it with them, to avoid the harmful cold that lies outside of their chosen homes. While this is not a power that a lava dragon can maintain for long, this allows them to travel further afield to gather treasure, food or revenge. Some other creatures who do not tolerate cold temperatures well have also learned this ability.

For a number of hours equal to its CR, a creature with this ability may ignore heat and cold dangers, in a sense being treated as if it were always in its preferred temperature. After this time, the creature automatically becomes fatigued (and immunity to fatigue does not render the creature immune), but can keep using the ability if it wishes. After another number of hours equal to its CR, the creature becomes exhausted instead (again, immunity won't help it). If the creature still wishes to continue to use the ability, it can last another number of hours equal to its CR, but after that, it'll fall unconscious, and this ability will deactivate.

If a creature starts off fatigued, exhausted, or unconscious, extended use of this ability will inflict the next-highest condition in the track (or, in the case of unconsciousness, simply not work at all). If the creature spends at least two hours in its preferred temperature zone, it can reduce the conditions applied by one step (unconsciousness to exhaustion, exhaustion to fatigue, fatigue to nothing).