At the main menu or pause menu, select the "Cheats" option. Then, enter one of the following codes to activate the corresponding cheat function:
|1 million DNA||cash|
|AI does double damage and player does half damage||hard|
|Fourarms alien form||classic|
|Rath alien form||primus|
|Upgrade all alien forms to maximum||upgrade|
Successfully complete the game to unlock the Fourarms alien form.