Spider-Man, Spider-Man! Sega Genesis Spider-Man!
This particular version of the game has become infamous in recent years for the sheer cacophony that is the Fun House theme.
Level Select#
The button check sequence is located at $011420-01154D.
While the game is playing in demo mode, hold D-Pad Down+Left and A. Tap the Start button, while keeping the other buttons held. The game loads a blank screen. Now, release the buttons, then enter Left, A, Right, Down, A, Start, Start (i.e., LARDASS).