Doom

Pause the game and press Up, Down, Left, Right, X, Z, Y, A, C, B.

First, pause the game and then press Up, Down, Left, Right, X, Z, Y, A, C, B.

Pause the game and press Up, Down, Left, Right, X, Z, Y, A, C, B.

Start a game and hit pause.

Press Down, Y, X, Right shift, Right, Left shift, Left, B to turn on God Mode

The following levels are not accessible through the "Level select" code. Game play will begin with 100% health, 0% armor, and the pistol with 50 rounds of ammunition.

When in the game pause and press:b,y,x,l,r,c,x,z for lots of goodies.

Pause the game and press Down, Y, X, R, Right, L, Left, B.

Former Soldiers: They resemble your old friends, but now they just fire pistols at you. They drop clips for the chaingun and pistol when killed.

Former Sergeants: Meaner and tougher. They carry shotguns and do more damage then soldiers. They drop shotguns when killed.

Imp: This creature throws fireballs and takes more bullets to kill.

Demon: Appear in most areas and can rip your head off if you are not careful. If you see more of them, use the chaingun.

Cacodemon: These creatures are ugly and have one big mouth. If they see you, they will fire lightning balls from their mouth. Use your rockets.

Mancubus: You have to use more then a chaingun to kill them. Use ammo with caution.

Arachnotron: Fires plasma energy at you. Use your rifle.

Spider Demon: The ultimate enemy. Has a super chaingun mounted on her body. Use your plasma rifle or rocket launcher.

Pause the game and press Down, Y, X, R, Right, L, Left, B.

Pause the game and press Right, Left, Z, R, Z, L, Z, C. Press Left and Right to select a level, and confirm your entry with B, C, or X.