Level Select (with Sonic 3 locked on):
Go to the first level and play until you get to the vines. Jump on and press left, left, left, right, right, right, up, up, up. A ring will confirm. Press Start then A to reset the game. At the title screen select the new option Sound Test.
Debug Mode (with Sonic 3 locked on):
Perform the Level Select cheat. At the Sound Test menu select the 7th stage with sonic and proceed to the pulley systems. Jump on and press left, left, left, right, right, right, up, up, up. A ring will confirm. Press Start and A to reset the game. FROM THIS POINT FOWARD YOU MUST HOLD A, B, AND C! Go to the Sound Test menu and select a stage when the stage is completly loaded you may let go of a, b, and c.
New Controls for Debug Mode
Sonic Mode: Jump
Debug Mode: Toggle through various items
B: Switch from Debug to Sonic Mode or vice-versa
Sonic Mode: Reverse Gravity
Debug Mode: Duplicate the current item.
(supplied by: Neo7)