Action Nuk'em Mode When "Press Start" appears at the opening screen, press Down(2), A, Z(2), Left, A. If you entered the code correctly, you will hear a sound. Alternatively, successfully complete the game to unlock Action Nuk'em mode, which allows Duke to kill opponents with one shot.
All Weapons When "Press Start" appears at the opening screen, press Down, A, Up, L, Z, R, C-Up, C-Down, B, C-Left. If you entered the code correctly, you will hear a sound.
Big Gun Mode When "Press Start" appears at the opening screen, press C-Up, C-Left, Z, B, L, Z, A. If you entered the code correctly, you will hear a sound. Alternately, kill all opponents in level 3, "Nuclear Winter", to unlock the cheat option for big gun mode.
Big Head Mode When "Press Start" appears at the opening screen, press B, Up, Down(2), A, Z, A, Right. If you entered the code correctly, you will hear a sound. Alternately, rescue all babes in level 2, "Liberty Or Death", to unlock the cheat option for big head mode.
Bonus Multi-player Characters Successfully complete any level and save the game to unlock one additional character in multi-player mode.
Debug Mode When "Press Start" appears at the opening screen, press C-Up, Up, C-Left, Right, C-Down, Down, C-Right, R, A, B. If you entered the code correctly, you will hear a sound. The "Cheats Menu" will be available but will have no cheats active (unless they were previously activated or earned). Once you start or load a game/level, text will appear in the upper/left hand corner of the screen. Use controller two to control the debug options. Press Start to cycle through the various lists of options. Use the buttons noted below to change certain values. Note: Debug mode does not save on the memory pak like the other cheats.
SFX
L or R: FX down/up
Left or Right: FX down/up by 10
B: First person view
A: Third person view
Z: Play SFX
Level Warp
L or R: Level down/up
B: Skip level
Z: Advance to selected level
Midi
L or R: Song down/up
A: Play song
B: Stop song
Global Palette
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
Cheat
Z: All weapons
L: All items
R: All keys
A: Invincibility
AI Debug Values
B or A: GVAR 1 down/up
C-Left or C-Down: GVAR 2 down/up
C-Up or C-Right: GVAR 3 down/up
Fog*
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
Left or Right: NR down/up
L or R: FR down/up
Sky Top*
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
Sky Bottom*
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
Clouds 1*
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
L or R: HT down/up
Down or Up: AN down/up
Left or Right: SP down/up
Clouds 2*
B or A: Red down/up
C-Left or C-Down: Green down/up
C-Up or C-Right: Blue down/up
L or R: HT down/up
Down or Up: AN down/up
Left or Right: SP down/up
Player
L or R: DN Down/Up (changes player's character)
GFX
(Values cannot be changed)
AI
A: AI 0/1 (set to 1 to stop enemies)
L: Difficulty 0/1/2
R: Auto aim 0/1
Alpha Palette
B or A: R0 down/up
C-Left or C-Down: G0 down/up
C-Up or C-Right: B0 down/up
L or R: R1 down/up
Left or Right: G1 down/up
Down or Up: B1 down/up
Weather Cheat works the same way but only has the options noted with an *
Extreme Mode Successfully complete the game with all babes rescued and all opponents killed to unlock Extreme mode, which allows the game to be played at a higher difficulty setting.
First Person View When "Press Start" appears at the opening screen, press Down, Up, L, B, Z, Left, C-Up, C-Right, C-Left, Z. If you entered the code correctly, you will hear a sound.
Flat Shade Map When "Press Start" appears at the opening screen, press Down, Up, Left(2), A, Right, Down. If you entered the code correctly, you will hear a sound. Alternately, obtain all secrets in the "Wetworld" secret level to unlock the cheat option for flat shade map.
Freeze Thrower With Infinite Ammunition When "Press Start" appears at the opening screen, press Down, Up, A, L, R, Z. If you entered the code correctly, you will hear a sound.
Going Down Level Collect all the time machine pieces before reaching "The Rack" level. Then a second exit portal will appear in the room just off where the first is located. Use it to reach the "Going Down" (Titanic) level.
Group 1 Multi-player Characters When "Press Start" appears at the opening screen, press A, L, R, Left, B, Down, Up to unlock all Group 1 multi-player characters. If you entered the code correctly, you will hear a sound.
Group 2 Multi-player Characters When "Press Start" appears at the opening screen, press B, A(2), R, L to unlock all Group 2 multi-player characters. If you entered the code correctly, you will hear a sound.
Group 3 Multi-player Characters When "Press Start" appears at the opening screen, press L(2), Up, Down, R, B, A to unlock all Group 3 multi-player characters. If you entered the code correctly, you will hear a sound.
Group 4 Multi-player Characters When "Press Start" appears at the opening screen, press B(3), R, Left, A to unlock all Group 4 multi-player characters. If you entered the code correctly, you will hear a sound.
Group 5 Multi-player Characters When "Press Start" appears at the opening screen, press Right, B, Left, L, A, Z to unlock all Group 5 multi-player characters. If you entered the code correctly, you will hear a sound.
Group 6 Multi-player Characters When "Press Start" appears at the opening screen, press Up, Down, B, A(2), Left to unlock all Group 6 multi-player characters. If you entered the code correctly, you will hear a sound.
High Speed Zombies When "Press Start" appears at the opening screen, press A(2), Z, A, R, C-Down, B. If you entered the code correctly, you will hear a sound. Alternately, rescue all babes in level 8, "Dry Town", to unlock the cheat option for high speed zombies.
Ice Skin When "Press Start" appears at the opening screen, press B, Z, Up, L, A, C-Right, A. If you entered the code correctly, you will hear a sound. Alternately, rescue all babes in level 5, "Fallout", to unlock the cheat option for ice skin.
Maximum Blaster Ammunition Kill all opponents in level 9, "Jailbreak", to unlock the cheat option for maximum blaster ammunition.
Maximum Freezer Ammunition Kill all opponents in level 20, "The Brothers Nukem", to unlock the cheat option for maximum freezer ammunition.
Maximum Gamma Ammunition Rescue all babes in level 21, "Alien Mothership", to unlock the cheat option for maximum gamma ammunition.
Maximum Gatling Gun Ammunition Kill all opponents in level 16, "Hydrogen Bomb", to unlock the cheat option for maximum gatling gun ammunition.
Maximum Revolver Ammunition Kill all opponents in level 12, "Probing The Depths", to unlock the cheat option for maximum revolver ammunition.
Maximum Rifle Ammunition Rescue all babes in level 11, "Ft. Roswell", to unlock the cheat option for maximum rifle ammunition.
Maximum SMG Ammunition Obtain all secrets in level 15, "Dawn Of The Duke", to unlock the cheat option for maximum SMG ammunition.
Maximum Sawn-off Shotgun Ammunition Kill all opponents in level 13, "Whitechapel Killings", to unlock the cheat option for maximum sawn-off shotgun ammunition.
Maximum Shotgun Ammunition Rescue all babes in level 10, "Up Ship Creek", to unlock the cheat option for maximum shotgun ammunition.
Maximum Sniper Ammunition Rescue all babes in the "Going Down" secret level to unlock the cheat option for maximum sniper ammunition.
Maximum Volt C. Ammunition Obtain all secrets in level 17, "The Rack", to unlock the cheat option for maximum Volt C. ammunition.
Refill Health Destroy a fire hydrant, or another water source. Then, stand in the water and hold A to slowly restore health. Alternatively, stand in front of a toilet or urinal and press A.
Rifle With Infinite Ammunition When "Press Start" appears at the opening screen, press C-Up, C-Down, C-Left, C-Right, L, R. If you entered the code correctly, you will hear a sound.
Skin Select When "Press Start" appears at the opening screen, press C-Left, R, Left, Up, Down, B, A, Z. If you entered the code correctly, you will hear a sound. Skins may be selected in single player mode, but may not be viewed during selection.
Weather When "Press Start" appears at the opening screen, press Z, A, L, B, Down, Up, R. If you entered the code correctly, you will hear a sound. Alternately, obtain all secrets in level 6, "Under Siege", to unlock the cheat option for weather.
Wetworld Level Play through the "Nuclear Winter" level until reaching the rail tracks leading to the communicator. Then, power up and drop off onto the roof below where a medi-kit can be seen. Jump off this roof into the water (which is only on one side). Swim to a floating platform, where the level exit will appear.
