Dr. Starline is back to his evil antics! But to enact his latest scheme he'll have to get into an abandoned Dr. Eggman base and past an army of badniks! To do that, he'll need the help of some of Sonic's greatest enemies! Mimic, Rough, Tumble, and Zavok are back and badder than ever! Then, Hold on to your chili dogs, Sonic fans! The Metal Virus is gone, but things aren't back to normal. Omega is damaged, and his allies turn to Team Sonic for help. The only way to rebuild him is to trade parts with a mysterious champion Chao racer, so it's off to the races for Cream, Cheese, Amy, and Rouge!