All weapons and armor:
Note: This code requires a six button controller. Press B + C + Y + Z during game play.

Invincibility:
Note: This code requires a six button controller. Pause game play and press X + Y + Mode + Up.

All weapons:
Note: This code requires a six button controller. Pause game play and press A + C + Mode + Up at the same time.

Invincibility, full health:
Note: This code requires a six button controller. Pause game play and press Up + Mode + X + Z. Note: Game play may not progress past level 15 if this code is enabled.

All weapons, full ammunition, all keys:
Note: This code requires a six button controller. Pause game play and press A + B + C + X + Y + Z . Note: Game play may not progress past level 15 if this code is enabled.

Weapon select:
Note: This code requires a six button controller. Press one of the following controller combinations to activate the corresponding weapon.

Weapon	Code
Chainsaw	Mode + Start
Pistol	Mode + A
Shotgun	Mode + B
Chaingun	Mode + C
Rocket Launcher	Mode + X
Plasma Rifles	Mode + Y
BFG 9000	Mode + Z

Hint: Enemies:

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.