A true, classic Sonic experience: Gorgeous pixel graphics featuring a variety of new Zones with iconic favorites from Sonic 1, 2, 3, Sonic & Knuckles and Sonic The Hedgehog CD Definitive version: Pristine, high quality HD version to enjoy Sonic and his friends as they face off against Dr. Eggman and his new robo-henchmen the Hard Boiled Heavies New characters join the fun with Sonic All-new Encore mode New and improved features including Competition mode