When you trigger the Kops, it doesn’t immediately summon massive swarms of them all at once. Instead, it triggers an effect that lasts 50+d50 turns, which causes one Kop to spawn on the upstairs and downstairs each turn, and occasionally on random spaces. Reconciling with the angry shopkeeper cancels the remaining duration of the effect and vanishes any existing Kops on the level.

This might have odd interactions if you leave the level while Kops are still spawning. Perhaps it should internally be tied to the level structure, not the player or a global variable; the effect would be suspended while off the level and resume once you reentered it.