With Dr. Eggman's grand schemes thwarted, it seems like all is well in the world, right? Wrong! Chaos is still alive, and has had it with being Eggman's pawn. Angel Island again crashes into the ocean, despite Knuckles' success at restoring the Master Emerald. The liquid monster makes it's move, stealing back the six Chaos Emeralds that Knuckles had retrieved from their encounter on the Egg Carrier.<br /><br />The events of the falling island do not go unnoticed by Tails, who informs Sonic of the disaster. The two immediately head for the alter of the Master Emerald, only to find both Knuckles and Eggman knocked out. After Knuckles wakes up and explains what happened, Sonic and Tails quickly realize they need to find the last Emerald in order to stop Chaos. Just as they are about to take off, the strange light orb appears to once again show a vision of the past...<br /><br />When Sonic comes back to reality, a worried Tails explains that the remaining Emerald is still on board the Tornado II. Somehow, Tails knows the aircraft is in the Mystic Jungle, despite having abandoned the plane when the Egg Carrier went down. Our heroes race to the jungle to retrieve the Tornado II and the last Emerald, but Chaos gets to the Emerald first.<br /><br />Now in his perfect form, Chaos unleashes his fury on Station Square, turning the city into a massive flood zone. Sonic arrives too late to stop the devastation, but is able to use part of the Chaos Emerald energy to transform into Super Sonic. The stage is set for the final showdown, and only one of these Emerald-powered entities will emerge victorious!