On the titlescreen, press and hold UP, A and B on controller 1 and DOWN, A and B on controller 2 at the same time to activate the level select. If done correctly a stage select menu should appear on top of
the screen. Levels are selected by pressing the B button. Press SELECT to activate he "TEST" mode which makes the player invincible.
On controller 2, press and hold A, B and SELECT on the titlescreen to enter the sound test mode.