Duke Nukem 3D Cheats - Sega Saturn

Controller debug
Hold [X] + [Y] + [Z] + [L] + [R] at the main menu screen until the phrase "Info Mode: On" appears. Debug information will appear at the top of the screen during game play.

Invincibility
Pause game play and press [X], [Z]x2, [X], [Y], [X], [Y], [Z], [Y].

All weapons
Pause game play and press [Z], [X]x2, [Z], [Y], [Z], [Y], [X], [Y].

Level select
Press [X], [Y], [Z]x2, [Y], [X], [Y], [Z], [Y] at the main options screen.

No monsters
Pause game play and press [Z]x2, [X]x2, [Y], [X], [Y], [X], [Z] at the skill level selection screen. A new "No Monster" skill level will become selectable.

Death Tank Zwei mini-game
Save a game from Quake or Powerslave onto the Saturn's internal memory or an external memory card. Alternatively, destroy all water sources, such as toilets and urinals in the entire game.

Jevons control mode
Note: This code requires an analog controller. Pause game play and press [Y]x2, [Z]x2, [X]x2, [Y], [X], [Z]. The phrase "Jevons Control: On" will appear when game play is resumed to confirm correct code entry. The new controller functions are:

[Analog-pad]: View direction
[A]: Action
[X]: Item
[B]: Move back
[Z]: Move forward
[Y]: Slide left
[C]: Slide right
[L]: Weapon
[R]: Jump
[Up] or [Down]: Item select
[Left] or [Right]: Weapon select

Easy health
Go to any water source such as a toilet or fire hydrant and destroy it. Go up to it and press [Action]. Keep pressing the button until your health is full.

Death Row: Items
Go to the chapel with two stained glass windows in the back. Enter the room and turn the first corner. Look up to see a man hanging from the roof. Shoot him to get a Atomic Health.

Stadium: Items
Look up to see a "DUF BEER" blimp. Destroy it up to get lots of items.

Urea 51
In the level after Rabid Transit, there is a television station. Inside is a room with a big red curtain that you can walk through. To the left there is a bathroom with two urinals, a toilet, and an "Out of Order" stall. The stall is a fake, with a secret level behind it. To open the door, unlock the red, blue, and yellow key card doors. When you open the final door (red), a crack will appear on the back wall. Blow up the crack and jump through to the "Auto Destruct" button. Instead of pushing the button, go back to the "Out of Order" stall in the television station. The stall should now be open, with a teleporter inside. Go through the teleporter to the secret bathroom with urinals along the walls. At the end of the hall is a "Auto Destruct" button to be teleported to the exclusive Saturn-only level, Urea 51 (which is a level full of toilets).