DEPARTMENT ZERO

Survive enemy waves across 6 departments. Every kill earns Tokens — spend them on weapons, consumables, and extra lives between floors.
Descend from Department 5 to Department 0. Each floor gets harder, but you get richer and more dangerous. The Nurse heals enemies on every floor.
Reach Department 0, defeat Devil Man, claim the Keycard, and escape. Lose all your lives and the run is over.