Doom Cheats...
All Baron Enemies
Pause the game and press Up, Down, Left, Right, X, Z, Y, A, C, B.
Cheat
When in the game pause and press:b,y,x,l,r,c,x,z for lots of goodies.
God Mode
Pause the game and press Down, Y, X, R, Right, L, Left, B.
Level Select
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.
Map All Items
Pause the game and press B, B, C, Right, B, B, C, Left.
Map All Lines
Pause the game and press B, B, C, Left, B, B, C, Right.
All Baron Enemies ...