Exhaustion

Exhaustion is a unique and unavoidable debuff that serves as the game's built-in timer for combat encounters. It deals 1 unblockable damage per stack at the start of the unit's turn, then increases its stack count by 1. Additionally, Exhaustion reduces all mana and health gain by 1 per stack and completely disables combat regeneration. Exhaustion cannot be removed by any means once applied, making it a permanent and escalating threat that eventually kills any unit that remains in combat too long.

Under normal conditions, Exhaustion begins applying at round 10 of combat. Old cats trigger Exhaustion earlier at round 5, and cats with the Insomnia disorder begin Exhaustion at round 3, drastically shortening their combat window. The Adrenaline buff can delay Exhaustion's onset by holding it at 0 stacks: when Exhaustion would normally activate, Adrenaline keeps the cat going with boosted crit and block chance instead. Each stack of Adrenaline provides one additional turn before Exhaustion takes hold.

Exhaustion creates strategic pressure to end fights quickly rather than playing defensively. Once it begins, the damage ramps up as a triangular number sequence (1, then 2, then 3, etc.), meaning each additional round becomes dramatically more dangerous. The healing reduction compounds this by making sustain strategies increasingly ineffective. Builds that rely on long fights or stalling tactics need to account for Exhaustion's inevitable arrival. In practice, most well-built teams should aim to finish combat before round 10 to avoid Exhaustion entirely, reserving Adrenaline-granting effects for emergencies or extended boss fights.