Invulnerability:
     Enter Down, Down, Right, Up, Left as a code.
     
All Multi Player Characters:
     Enter Left, Down, Left, Right, Down as a code.

Big Head Mode:
     Enter Down, Up, Left, Right, Right as a code.

Dragon Warrior Outfit:
     Enter Left, Down, Right, Left, Up as a code.

Infinite Chi:
     Enter Down, Right, Left, Up, Down as a code. 

4x Damage Multiplyer:
     Enter Up, Down, Up, Right, Left as a code.

All Outfits:
     Enter Right, Left, Down, Up, Right as a code. 

Full upgrades:
     Enter Left, Right, Down, Left, Up as a code.