*Based on Knuckles' Chaotix* After Sonic Chaos, tectonic movement in the South Sea caused by the Master Emerald's energy causes a mysterious island to emerge. The island rapidly transforms into a lush landscape with the Emerald's power. Dr. Ivo "Eggman" Robotnik investigates the island and learns that it used to be home to a lost civilization after finding a ring with ancient characters inscripted on it. The mysterious space created by the ring's power is filled with Chaos Emerald energy that has materialized into six objects called "Chaos Rings". Eager to research on the Giant Ring to harness the Master Emerald, the doctor sets up camp on the island, which he transforms into a resort dubbed Newtrogic High Zone. Meanwhile, Knuckles the Echidna, curious about the island's nature and driven by a sense of responsibility as the guardian of the Master Emerald, arrives on the nearby Isolated Island, where he meets Espio the Chameleon. Espio introduces Knuckles to Vector the Crocodile, Charmy Bee, Mighty the Armadillo and Ray the Flying Squirrel, who together make up the Chaotix Detective Agency. Eventually, the heroes encounter and defeat Metal Sonic. In a last-ditch effort, Eggman transforms Metal Sonic into Metal Sonic Kai!
