Sonic The Hedgehog [Model 52]

* Level Select : At the title screen, press Up, Down, Left, Right. You should hear a noise like a ring being collected. Then, hold A and press Start for a level select.

* Crazy Sonic : Hold A+B+C during demonstration mode for force Sonic to run into objects and act strangely (Note : This may also be done during the ending sequence after completing the Final Zone).

* Debug Mode : Press Up, C, Down, C, Left, C, Right, C, Start, then hold A at the title screen. Continue to hold A until game play begins. Screen coordinates will appear instead of a score and the number of objects displayed will appear instead of the time remaining. Use one of the following buttons sequences to enable the corresponding debug code...
Object transformation : Press B during game play to change Sonic into a game object.
1) Press A to change into a new object.
2) Press C to place an object on the screen.
3) Press B again to revert back to Sonic (Note : The type of object that may be selectable will vary from level to level).
Invincibility : Sonic is, by default, invincible in debug mode (Note : Sonic can still drown, be crushed, fall and die, etc. He is only invincible to enemy attacks).
Slow motion : Pause game-play and hold B.
Restart : Pause game-play and press A.
Frame advance : Pause game-play and press C.

* Control Ending Sequence : Enable the 'Debug mode' code. Press B when Sonic is running with the animals at the end, then turn back into Sonic. You can now control yourself.