Knuckles in Sonic 2 Green Hill Zone by Hivebrain V0.2 (SK Hack) - Genesis - Platformer

Knuckles in Sonic the Hedgehog is a fan-made ROM of the game Sonic the Hedgehog for the Sega Mega Drive/Genesis, featuring the character Knuckles the Echidna in place of Sonic the Hedgehog, the game's usual protagonist.