Main game concept, Journeys in the Dark
I - Rules
(see JITD, p. 17-18)
Fatigue is spent by returning the fatigue token or tokens to the pile of unused tokens in the common play area. Once a hero is out of fatigue tokens, he may not spend fatigue again until he has used the rest order or another method to regain some of his fatigue. Fatigue may be spent in two ways.
Spending Fatigue for Movement - At any time during a hero's turn, he may spend one fatigue to gain one movement point, even if he is currently taking the battle action. This may be done as often as the hero desires. Movement points gained in this manner are spent just like normal movement points.
Spending Fatigue for Attacks - After rolling an attack, a hero may spend one fatigue to roll one additional power die, adding its result to the roll. This may be done as often as the hero desires, one die at a time.
Road to Legend
There are only 24 fatigue tokens included in the core box of Descent and none added in the expansions. Shortage of fatigue tokens is a problem with the Secret Trainings. For example, if the 4 heroes have a base speed of 5 and each of them would like to increase their fatigue by 2 at each level of the Advanced Campaign, one would need 44 fatigue tokens. If a hero also has the skill Skilled, one would need 46 tokens.
There is no clear official rule resolving this problem so far. Some players use substitute tokens and some others state that 24 is the limit available and that the heroes should plan their strategy accordingly.