Press ~ during game play to display the console window, then type sv_cheats 1 to enable cheat mode. Then, enter one of the following codes at the console window to activate the corresponding cheat function. Note: Cheat codes cannot be enabled during in offline practice.
Use the [~] key during gameplay and type in "sv_cheats 1" to enable cheat codes, then enter any of the following commands (can not be used in offline practice):
Use map 7 of the original campaign to get hundreds of bugs to kill. You can also try map 3, with the the flying flashlight. Get a grenade launcher and start killing them.
Created by theironpaw.
To unlock the promotion stars reach level 27 and hit promote. It will reset your levels, but you will have the promotion stars.