Sonic and "Tails" thought that they had destroyed the Death Egg, which was Dr. Robotnik's heavily armored ship. Instead, Dr. Robotnik managed to crash land on the Floating Island. After learning that the island is able to float in the sky by harnessing the power of the emeralds, the Doc decides to steal the emeralds so he can repair his Death Egg ship.

To obtain the emeralds, Dr. Robotnik tricks Knuckles, the guardian of the Floating Island's Chaos Emeralds. He also tells Knuckles that Sonic and "Tails" are the ones trying to steal the emeralds. Once Knuckles believes Robotnik's lies, he'll do whatever it takes to stop Sonic and "Tails".

Between battling the new types of Badniks and trying to outsmart Knuckles, Sonic and "Tails" have their work cut out for them once they arrive on the Floating Island and search for Dr. Robotnik.

Knuckles was born and raised on the Floating Island and he knows all of its secrets. He's strong, athletic and clever. Because Knuckles knows every hidden passageway on the island, it's easy for him to block Sonic's path, create extra obstacles, set traps, and steal Sonic's gold rings.

Long ago, an ancient civilization lived on the Floating Island. Before this civilization mysteriously disappeared, it left behind many secrets and mystical powers. Being the only living descendant of this lost civilization, Knuckles has become the guardian of the Chaos Emeralds, which are the source of the island's special floating power.

Fun facts about Knuckles

• Age: 15 Years Old
• Species: Echidna
• Favorite Foods: Fruit (especially grapes)
• Special Abilities: Discovering hidden passageways and using his knuckles to dig.