Enter the codes at the main menu. Cheat mode must be activated for the other codes to work.
Left, Left, L, L, Right, Right, Left, Left.
R, C-Right , Right, L, C-Left , Left, C-Right, Right.
R, R, R, R, R, R, R, Left.
L, C-Left, Left, R, C-Right, Right, Left, Left, Right.
L, L, L, C-Right, Right, Left, Left, C-Left.
First at the main menu do the master code (Up, C-Up, Left, C-Right, Down, C-Down, Right, C-Left). Then make a dukebot battle and make it so you dont have a time limit and not a survivor game. Then make sure it is in the level Overlord to make it easy. When you start go to the cheats and put all items on and then unpause it. Go next to a wall and kill yourself with any explosive weapon. Pause it and put invincibility on then off. You are now dead duke (this means dukebots can't see you). Now you can kill lots and lots of dukebots. My record is 1100 toasted.
(supplied by: zombiekiller)