Select "Options" at the main menu. Select "Cheat", then enter one of the following codes to activate the corresponding cheat function. Note: Enabling codes will disable game saves. that you will be unable to save upon activation.

Effect	Code
All characters in multiplayer mode	CAST
All costumes	WRDB
All weapons in multi-player mode	DKSD
All weapons in single player mode	GTSM
Level select	RMTE
Maximum money	PWTR
One shot kills	MNKY
Unlimited ammunition	GGTY