Sonic the Hedgehog 3

Story

After Sonic defeats Dr. Robotnik at the end of Sonic the Hedgehog 2, his space station, the Death Egg, crashes on a mystical floating landmass called Angel Island (or simply "the floating island" as it is called in the game manual). As Dr. Robotnik begins to repair the damaged station, he meets Knuckles the Echidna, the last surviving member of an ancient Echidna civilization that once inhabited the island. He is also the keeper of the master emerald that gives the island its levitation powers. Dr. Robotnik knows that Sonic and Tails will try to track him down, and he knows that he can use the Master Emerald to power the ship, so he tricks Knuckles into thinking that Sonic is trying to steal his Emerald. A short time later, Sonic and Tails are in their biplane, the Tornado, looking for Dr. Robotnik. Sonic, who has the Emeralds from Sonic 2, then transforms into Super Sonic. Once they arrive, Knuckles ambushes Sonic and knocks the Chaos Emeralds out of his hand, returning him to normal. Knuckles steals the Emeralds and disappears inland. As Sonic and Tails travel through the levels, they encounter Knuckles in almost every level, who prevents them from progressing. In the final level, the Launch Base Zone, Death Egg launches for the second time, knocking Knuckles off a pole and sending him crashing into the water. Sonic travels to a platform on the Death Egg, fights Robotnik and defeats him for the last time. The Death Egg is damaged and crashes back onto Angel Isle after Robotnik's defeat - and thus begins the second half of the story in Sonic & Knuckles.