Sonic the Hedgehog Sonic the Hedgehog Sonic the Hedgehog is a video game franchise produced by Sega centering on a series of high-speed platform games. Sonic, the protagonist, is an anthropomorphic blue hedgehog with supersonic speed. Typically, Sonic must stop antagonist Doctor Eggman's plans for world domination, often helped by his friends, such as Tails, Amy, and Knuckles. The first "Sonic the Hedgehog" game, released in 1991, was conceived by Sega's Sonic Team division after Sega requested a mascot character to compete with Nintendo's mascot Mario. Its success spawned many sequels and helped Sega become one of the leading video game companies during
Sonic the Hedgehog 2 was released in 1994, two years after "Sonic 2". The "Sonic & Knuckles" game cartridge features a special "lock-on" port into which the player can insert other Genesis cartridges. Attaching "Sonic 2" unlocks "Knuckles the Echidna in Sonic the Hedgehog 2", a variation of "Sonic 2" whereby the player plays as Knuckles the Echidna, a character introduced in "Sonic the Hedgehog 3" and not playable until "Sonic & Knuckles". Though the game is largely identical to "Sonic the Hedgehog 2", Knuckles is able to glide and climb walls, allowing him access to areas previously inaccessible to Sonic or Tails. However,