Zeke is a skeleton
Hold [X] + [Circle] + [A] + [Triangle]
at the opening sequence, before the legal screen. Release the
buttons at the title screen.
Zeke is invisible
Hold [X] + [Square] + [L1] + [R1]
at the opening sequence, before the legal screen. Release the
buttons at the title screen.
Invincibility
Hold [Right], then press [Square], [Circle]x3,
[Square], [Circle], [Triangle], [X] during
game play.
Weapon upgrade
Hold [Right], then press [Square]x2, [Triangle]x2,
[Circle]x3, [X] during game play.
Level select
Hold [Right], then press [Circle]x2, [Square],
[Triangle]x2, [Square], [Circle], [X] during
game play.
Full health
When low on health, save then quit the game. Reload
the saved game to resume with your health restored.