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[edit] PC

Cheats for the PC version are typed on the keyboard. Note that some cheats may conflict with your key bindings, resulting in secondary effects (such as using steroids, etc.)

Code	Effect
DNALLEN	Displays "BUY MAJOR STRYKER" message
DNBETA	Displays "PIRATES SUCK!" message
DNCASHMAN	Throw money when the use/open button is pressed
DNCLIP	Toggles no-clip mode (walk through walls)
DNCOORDS	Displays current coordinates
DNCORNHOLIO or DNKROZ	Toggles God mode (invincibility)+ unlimited jetpack
DNCOSMO	Displays "REGISTER COSMO" message (Version 1.3d and prior only)
DNDEBUG	Displays debug information (upper left corner)
DNDEBUG	Adds night-vision goggles and steroids; uses steroids
DNINVENTORY	Adds all items and body armor
DNITEMS	Adds all items, keys, and armor
DNKEYS	Adds all keys to inventory
DNMACS	Change security screens to Macintosh desktops (Mac version only)
DNMONSTERS	Toggle monsters (monsters will spawn and immediately disappear)
DNRATE	Shows framerate
DNSCOTTY<episode(1-4)+level(01-11)>	Warp to another level, i.e. DNSCOTTY205
DNSHOWMAP	Reveals map
DNSKILL<level 1 - 4>	Change skill level; restarts level, i.e. DNSKILL3
DNSTUFF	All items, weapons, keys, ammo, and armor
DNTODD	Show "REGISTER COSMO" message
DNUNLOCK	Toggles all lockable doors, forcefields, etc.(only in registered version) Note: will lock normally-unlocked doors that have a lock on them.
DNVIEW	Changes to third-person View
DNWEAPONS	All weapons and ammo
DN1984	Works only in Hollywood Holocaust level 1, Mac version only. Causes 1984 Macintosh ad to play on the movie screen.

[edit] Nintendo 64

Cheats are input through a cheat menu. To activate everything, enter at the main menu:

To activate individually, first activate the cheat menu with:

Then, use the following codes at the main menu to enable individual items:

Code	Menu item
	All items
	Invincibility
	No monsters
	Level select

Like the PC version, invincibility gives an unlimited jetpack. Unlike the PC, it blocks shrink rays. As such, you'll need to disable it for parts of the level requiring you to shrink.

Only invincibility works at the main menu. To use the others, go into the game. Press for the pause menu. Go to the cheats submenu, enable the appropriate codes, and press again to return to the game.