Power Up mode: Press Up, Right, Left, Down,
Up, Right, Left, Down at the title
screen. Rotate the Joystick clockwise in two circles to
give Bub and Bob permanent shoes, blue gum, and yellow gum.
Super mode: Press Left, Start, Fire, Jump,
Up, Down, Start, Right at the title
screen to unlock another set of levels.
Original mode: Press Start, Left, Fire, Jump,
Fire, Jump, Fire, Jump. Secret rooms
will always appear in levels 7 and 37.
