



The unique cartridge featured " Lock-On Technology" and allowed players that also owned the game Sonic the Hedgehog 2 to link the two together and play the game through as Knuckles instead of Sonic. The history of the game begins with the release of the Mega Drive game Sonic & Knuckles. Knuckles in Sonic the Hedgehog is a fan-made ROM of the game Sonic the Hedgehog for the Sega Mega Drive, featuring the character Knuckles the Echidna in place of Sonic the Hedgehog, the game's usual protagonist.
