Sonic the Hedgehog 2 is, of course, the sequel to SEGA's immensely popular action-adventure and platforming game Sonic the Hedgehog. As part of his plot to conquer the world, Dr. Robotnik has once again kidnapped adorable animals to power his doomsday robots. It's up to Sonic, the world's fastest hedgehog, to save all his friends and bring Dr. Robotnik down. This time, though, Sonic has a partner: Tails the flying fox. Together, the two heroes are off to save the day, blazing through eleven levels at speeds only Sonic could achieve.