Unlock Gravity Gun:
During gameplay when you have the SMG equipped press Down, Up(2), Down, L, R, X, B, A. If the 'Organic Gravity Gun' code is activated this code cannot be enabled.

Unlock Organic Gravity Gun:
During gameplay when you have the Gravity Gun equipped press L, Black, R, White, Up, Down, Y, X, B, A. If the 'Inorganic Gravity Gun' code is activated this code cannot be enabled.

Unlock ALL Chapters:
Left, Left, Left, Left, Black, Right, Right, Right, Right, White

Restore 25 Points of Health:
During gameplay enter Up, Up, Down, Down, Left, Right, Left, Right, B, A.

Restore Ammo for current Weapon:
During gameplay enter Y, B, A, X, White, Y, X, A, B, White.