While playing Single-Player, press the tilde (~) button
and type in any of the following codes:


Code            Result
----------------------
vivalahelvig  - Invulnerability
bighugmug     - Full Ammo/All weapons
heehoo        - Fly Mode
kill          - Suicide
camera1       - switch camera modes
camera2       - switch camera modes
camera3       - switch camera modes

NOTE: In certain parts of the game, invulnerabilty may
switch off when moving into a new area.