Harsh conditions or long exertions do not easily tire you.
You gain a +4 bonus on the following checks and saves: Swim checks made to resist nonlethal damage from exhaustion; Constitution checks made to continue running; Constitution checks made to avoid nonlethal damage from a forced march; Constitution checks made to hold your breath; Constitution checks made to avoid nonlethal damage from starvation or thirst; Fortitude saves made to avoid nonlethal damage from hot or cold environments; and Fortitude saves made to resist damage from suffocation.
You may sleep in light or medium armor without becoming fatigued.
A character without this feat who sleeps in medium or heavier armor is fatigued the next day.
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SECTION 15