Completion bonuses
Finish the game in the easy difficulty setting to access the special menu and movie mode.

Finish the game in the normal difficulty setting to access two player mode. When iIn this mode, one person moves using a Dual Shock 2 controller, while the other shoots with a GunCon2.

Finish the game in the hard difficulty setting to access the game art.

Finish the game in the normal difficulty setting with a rank "B" or greater without using any Resurrection Packs to unlock infinity mode.

Finish the game on Normal without using a resurection pack and attain at least an overall B grade at the end of the game.

Shoot credits
You can use your gun to shoot the ending credits.