From Archon Arcana - The KeyForge Wiki

The active player may use any ready creature of the active house to reap. When a player uses a creature to reap, the player exhausts the creature, gains 1Aember icon from the common supply, then all “After Reap:” abilities on the creature resolve.

Note: As of version 16.0 of the KeyForge Master Rulebook, all cards that have abilities that begin with “Reap:” should be read as “After Reap:”.

KeyForge Master Rulebook v17.3 March 2024