http://www.youtube.com/watch?v=D0vFYHpkZQI
A Full hack of Sonic the Hedgehog 1 for the Sega Genesis, with tons of Features, Brand New Levels, Playable Characters, and more
Credits:
Vladikcomper - Destroy Enemy = Ring code (only for Somari)
Hcktrox - Menu and Music
Nineko - Music
CS and Yuski - Metal Sonic Sprites
Quricodoido - few Music
GHFusion - Chaotix Music
Mercury - Editable Walljump sourcecode
Esrael - S2 Level Select
MarkeytheJester - Sonic Crackers Music
Selbi - Super Peelout
Tweaker - Sound Driver
I don't know if Roms are allowed here so I added a IPS Patch in case.
Metal Sonic Hyperdrive V1.0.zip
Metal Sonic Hyperdrive IPS.zip