Play as Sonic or Tails in Sonic Chaos, which was originally made for the Sega Master System. Dr. Eggman (a.k.a. Dr. Robotnik) has stolen the Red Chaos Emerald to create nuclear weapons. This has thrown the remaining Chaos Emeralds off balance, causing them to transport to a parallel universe.
As a result, Sonic's home, South Island, is sinking into the ocean. Speed through various levels in your crusade for the six Chaos Emeralds. Perform Strike Dashes and Super-Peel Outs as Sonic, or Spin Dash and Fly as Tails, and restore order in Sonic Chaos.