Knuckles the Echidna in Sonic the Hedgehog 2

Knuckles the Echidna in Sonic the Hedgehog 2 is a video game that can only be accessed by combining the Sonic & Knuckles cartridge with the Sonic the Hedgehog 2 cartridge. It allows you to play through the entire game of Sonic the Hedgehog 2 as Knuckles the Echidna. On Virtual Console, Knuckles the Echidna in Sonic the Hedgehog 2 is automatically available to play if both Sonic the Hedgehog and Sonic & Knuckles have been purchased.