Obscure Cheats

Laser-sight pistol
Complete the game under the normal or higher difficulty setting, then start another game in special mode. The first available gun will now be a pistol with a laser sight.
Submitted by: CoolM

FMV sequences
Complete the game to unlock a making of, behind the scenes, and two music videos.
Submitted by: CoolM

Alternate costumes
Complete the game, then start another game in special mode. Note: Only characters that survived will have an alternate costume.
Submitted by: CoolM

Special mode
Complete the game.
Submitted by: CoolM

Morgenstern bat
Complete the game, then start another game in special mode.
Submitted by: CoolM

Alternate menu background
Successfully complete the game.

Gallery 1
Successfully complete the game under the hard difficulty setting.

Gallery 2
Successfully complete the game in special mode.