Game Cheats:
On the main menu, edit the player name to be GOD (all in caps).Then either launch a new campaign or start a saved game. The saved games' player name must also be GOD. This cheat gives you invulnerability. The Player name must be changed to GOD each time the game is run.
Command line:
/KARMA = all weapons and equipment are made available. that's it
/US = ?
Invincibility:
Edit the player name from the main menu to GOD (case-sensitive), and
start a new campaign.
All weapons and equipment:
Start the game with the /karma command line parameter.