Bonus levels...
	Level Select...

Pause the game. Press and hold Z. Press C-Down, L, R, L, R, L, R, L, R, L, R.

Pause the game. Press and hold Z. Press R, B, A, B, A, C-Up, C-Down, C-Left, C-Right, C-Up, C-Down, C-Left, C-Right.