Type in the following codes during game-play to activate them
Invincibility: QUICKEN
Level Warp (## = Episode/level): ENGAGE##
All Weapons and Ammo: RAMBO
All Skeleton Keys: RAVSKEL
Turn into a Chicken: COCKADODDLEDOO

Changes the Map Mode (must be in map mode): RAVMAP

Walk through Walls: KITTY

Death Match Level: ENGAGE41

Full Health: PONCE

Toggles Power-Up Mode: SHAZAM
Kills All Monsters on the Level: MASSACRE

Toggle sound Debug information: NOISE

Toggles ticks-per-frame counter: TICKER
Instant Death: IDDQD

Get no Weapons or Ammo: IDKFA
Ring of Invulnerability: GIMMEA

Shadowsphere: GIMMEB

Quartz Flask: GIMMEC

Tome of Power: GIMMEE

Torch: GIMMEF

Time Bomb of the Ancients: GIMMEG

Morph Ovum: GIMMEH
Wings of Wrath: GIMMEI
Gives item that warps you to the beginning of the Level: GIMMEJ
Enter at game startup (to take pictures of the game at any time press F1): RAVPIC