Cheat Codes:at any time during a single-player campaign, press start and select ''in game options'' from the start menu. now select ''enter cheats'' and enter the following codes:
B,B,X,A-INVICIBILITY
B,B,X,B- TEAM INVINCIBILITY
B,B,X,Y-COMPLETE MISSION
B,B,X,X-REPLENISH AMMO