Press ~ while playing to display the console window. Enter the following codes:

Result -.- Code:

Return to life when killed -.- reincarnate
Scale player size; "2" is default -.- changesize (number)
Set gravity value -.- setgravity (number)
Set game speed -.- setspeed (number)
Teleport to targeting reticule -.- teleport
Toggle God mode -.- god
Unlimited ammunition clips for all guns -.- infiniteammo
All weapons will maximum ammunition -.- loaded
All weapons -.- allweapons
Breathe underwater for 999999 seconds -.- amphibious
Disable flight and no clipping modes -.- walk
Flight mode -.- fly
Freeze current screen for indicated amount of time -.- freezeframe (seconds)
Maximum ammunition for all weapons -.- allammo
No clipping mode -.- ghost

Level Select - For Level Select, complete the game in Campaign Mode under Easy difficulty.
Sent in by: Carlene