Cancer

Cancer is a rare trinket that applies a status effect after each battle ends. Like the Golden Egg, this is an end-of-fight reward rather than an in-combat tool — every victory stacks its effect onto your cat. The name suggests the status may be something persistent or spreading in nature, making it potentially stronger the longer a run goes on.

StatusOnBattleEnd passives fire once per fight after the last enemy is defeated, applying their effect to the wearer as a post-combat reward. If the status stacks additively over many fights, the wearer grows progressively stronger throughout a run in ways that compound with combat length. The Cancer name has biological connotations of uncontrolled growth, suggesting the status accumulates without a natural cap and becomes increasingly dominant late in a run when many stacks have built up.

Cancer is most powerful in long runs with many fights, where the accumulated stacks from dozens of victories create a significant passive bonus. Equipping it early maximizes the number of battles where it generates stacks. Unlike active trinkets that deplete, Cancer never runs out of charges and contributes passively to every fight cleared. The status type determines whether this is a damage, defensive, or utility benefit, but any build can take advantage of the compounding nature if the accumulation is meaningful per stack.