Sonic the Hedgehog different media including animation, comic books, and a Hollywood film. The first "Sonic" game, "Sonic the Hedgehog", is a platform game released in 1991. Players control the anthropomorphic blue hedgehog Sonic, who can run and jump at high speeds using springs, ramps, and loops. Sonic must stop Dr. Robotnik from taking over the world using the Chaos Emeralds. "Sonic the Hedgehog 2" (1992) increased the overall size and speed of the series' gameplay and was the second best-selling Genesis game. It introduced Sonic's sidekick and best friend, Miles "Tails" Prower, who followed Sonic throughout the game, and allowed a second
Sonic the Hedgehog collect one of the Chaos Emeralds. In "Sonic the Hedgehog 3", if all Emeralds have already been found, touching them rewards the player fifty rings. In most games since "Sonic Adventure 2", these giant rings serve as the end level marker, which ends the level upon touching it. Checkpoints are items placed throughout the stages in "Sonic" games which serve mainly as progress markers. If the player runs through one, their progress through a level is "saved". If the player then loses a life on the same stage, they will start over at the last checkpoint passed. Checkpoints also serve