Sonic 3 & Knuckles

Sonic 3 & Knuckles is a video game that can only be accessed by combining the Sonic & Knuckles cartridge with the Sonic the Hedgehog 3 cartridge (Sonic 3 in Europe). It allows you to play through both video games in a single playthrough as either Sonic the Hedgehog, Tails, Knuckles the Echidna, or as Sonic the Hedgehog and Tails in 2-player co-op mode. 2-player split-screen multi-player is also present, with both players able to select from the three main characters. On Virtual Console, Sonic 3 & Knuckles is automatically available to play if both Sonic the Hedgehog 3 and Sonic & Knuckles have been purchased, while on Steam both games were combined together as originally intended.