Cheat Mode

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