Sonic ERaZor is a fan-made game for the Sega Genesis. Without more information from its creators or online communities, details on its gameplay, plot, and origins are currently unavailable. The name itself is a slight variation on 'Sonic', hinting at a game possibly centered around fast-paced platforming,  a hallmark of the Sonic the Hedgehog series.  Information may be found on ROM hacking and Sega Genesis fan game websites.

Sonic ERaZor

Sonic Encore (early development version)