Press the console key ` and type "cht_bEnableCheats = 3" to enable the developer cheats. Note that console commands are case sensitive. Cheats are accessed through the menu (Press ESC followed by F3) or by typing them into the console. (Type "cht" into the console and press TAB for a list of cheats.) Note that cheats invalidate your achievements and leaderboard score gained in that session. Type "cht_bEnableCheats = 0" in the console to disable the cheats for the next session. Activate the following cheats by entering the corresponding codes:
Auto aim cheat.
Display all the messages in NETRICSA.
Enemies can't see you.
Fly around and pass through walls.
Gives a specified amount of ammo for a specified weapon.
Gives a specified amount of armor.
Gives a specified amount of health.
Gives a specified weapon.
Gives all available weapons and maximum ammo.
Greatly increased speed.
Kill all enemies in line of sight except for bosses.