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 player to control him in a limited fashion. This game also introduced Sonic’s “spin dash” maneuver, an ability which allows Sonic to burst forwards quickly from a complete standstill, unlike the previous game, where Sonic could only gain speed with momentum. Sonic 2 was followed in 1993 by an arcade game, SegaSonic the Hedgehog, featuring new characters Mighty the Armadillo and Ray the Flying Squirrel.