The third main game in the Sonic the Hedgehog series, it was released for the Sega Genesis worldwide in February 1994, and in Japan three months later. It was developed simultaneously with Sonic & Knuckles; as the games were originally developed as a single title until time constraints and cartridge...
The game is a sequel to the Sonic the Hedgehog 2 for the same system and follows on directly from the end of the game, in which Sonic defeated his enemy, Dr. Robotnik; crash-landing on a floating island, Sonic encounters new character Knuckles the Echidna, and must once more retrieve the Chaos Emeralds while also working to stop Dr. Robotnik from relaunching his ship, the Death Egg.