This hack was created by me and my friend Dawmer. we modified Sonic 1 mega drive to be a new game. many aspects like music, stages and layouts were changed. characters like Tails, Knuckles and Amy were also added.
To go to level selection, press 3 times back, 3 times up, down and forward.
It is also possible to play with Metal Sonic, but he is a secret character. to unlock it, you must go to the sound test and listen to these songs, 13,75,19,57 and then press start on the middle option called extra chars.