Sonic the Hedgehog 2
Note: This code has sensitive timing. Tails will blink his eyes once,
then two more times in quick succession. Hold Down/Left + 1 + 2 at the
title screen and wait until Tail blinks for the third time. Press Start
at exactly that moment, while Tails' eyes are closed. A sound will
confirm correct code entry. Use Up or Down to select a level and press
2 to begin game play.
Alternatively, hold Down/Left + 1 + 2 during the introduction sequence
and keep them held as the title screen is displayed. Release the
buttons after the sound of the bells are heard. Press Start to enter
the level selection screen.
Level select (European version):
Enter the sound test screen and play tracks 19, 65, 9, and 17 (in order).
Press Start to exit the screen. Wait until Sonic and Tails give a
"thumbs up" and press 1 + Start, Start.
Level passwords (European version):