Obscure Cheats

Unlock Hard Mode:
Clear the game successfully.
Unlock Special Mode:
Clear the game successfully.
Unlock Sum41 and Span Music Videos:
Clear the game successfully.
Unlock New costumes:
Clear the game (surviving characters only).
Unlock New weapons:
Clear the game (baseball bat and laser scoped handgun).

Complete the game, then start another game in special mode.

Successfully complete the game to unlock a making of, behind the
scenes, and two music videos.

Successfully complete the game to unlock a making of, behind the scenes, and two music videos.