Enter these on the passcode screen:

• TUSKFISH - Unlock All Missions
• BANNER - Invincibility
• WRASSE - Bullet Shield
• JAWFISH - Unlimited Ammo
• BATFISH - Silver Bullet
• CARDINAL - Achilles Head
• BOXFISH - All Replay Items
• PARROT - Invisible Soldiers
• DOTTYBACK - Men With Hats
• BETTA - Rubber Grenades