The following are known Action Replay Codes for Project Overkill on Sony Playstation (PS1).

The codes should work with the region specified but may work for other regions as well.

Device Compatibility: Action Replay, CodeBreaker & GameShark

Infinite Ammo P1
800997da0064

Have Green Key
8005bd9e0001

Have Orange Key
8005bda20001

Have Yellow Key
8005bda00001

Infinite Health P1
800997b60164

Infinite Ammo P1
800997dc6464
800997de0064

Digiprint Hand
8005bda40001

Scanner Eye
8005bd9c0101