First, complete the game to unlock the "Cheats" menu. Unlock the following cheat functions by performing the corresponding tasks in Time Trials:
CHEAT FUNCTION - HOW TO UNLOCK Full Armor - Start with full body armor. Does not replenish (1 XP). Tactical Knife - Start with a Tactical Knife (2 XP). Infinite Ammo - All weapons have unlimited ammo reserves (3 XP). SB-Y90 - Starts with a SB-Y90 gun equipped (4 XP). Universal Silencer - Gunshots and ricochets do not alert guards (4 XP). Proximity Charges - Start with Proximity Charges (4 XP). Silent Steps - Footsteps no longer alert guards (4 XP). .50 DLX - Start with the .50 DLX gun (4 XP). Invisible to Cameras - Become invisible to all cameras (4 XP). JM7 Rocket - Start with the JM7 Rocket (4 XP). Golden Gun - Start with the Golden Gun. kills enemies with a single bullet. (5 XP). Vanisher - When you defeat an enemy, they will disintegrate (6 XP).