At the main menu, press Circle, Left, Right, Circle, Up, R2. A "Cheat" selection will appear on the options screen, allowing God mode, all weapons, infinite ammunition, infinite oxygen, no chestbursting, and level selection.

At the main menu, press Square, Up, Down, Circle, Left, R1. A "Research Mode" selection will appear on the options screen. This mode allows you to change some of the games Aliens and Facehuggers (shrinking them, making them wire-framed, semi-transparent, etc.). This is done by highlighting various sequences of grid squares.