Here is a hack which changes all the level layouts, all the stage music, new graphics, and also some new power-ups! Now you can also do a quick spin-dash in the air with the cost of rings.
Sonic The Hedgehog (USA_ Europe).md - NOINTRO
CRC32: F9394E97
MD5: 1BC674BE034E43C96B86487AC69D9293
SHA-1: 6DDB7DE1E17E7F6CDB88927BD906352030DAA194
SHA-256: 46160BAA06362C711C9F1A5017CB7371026444936C8AF5E93A78996CF32FF2A6