Fatigue is an extension of the Stamina pool equal to half its size, meaning that if your character has twenty-four Stamina they can endure up-to twelve points of Fatigue. Fatigue sets in when the pool of Stamina is exhausted and the player continues to expend Stamina. For each point of Stamina expended below zero, the character assumes one point of Fatigue.
Characters recover Fatigue points at half the rate as their normal Stamina pool. When resting, Fatigue points must always be regained before usable Stamina may be replenished.