Sonic the Hedgehog
Due to the success of "Sonic" games on the Sega Genesis, the series was introduced to the Master System and the Game Gear. Sega began by releasing "Sonic the Hedgehog", a 2D platform game, in 1991. The game featured Sonic's ability to run and to jump at high speeds like its Mega Drive/Genesis counterpart but with notably different level design and music. Sega later released "Sonic the Hedgehog 2" another 2D platform game, in 1992. The game differed from its Genesis counterpart with different levels and music and by not including a "spin dash" maneuver. It also featured a different storyline in which Doctor Robotnik kidnaps Tails, who is non-playable in the Master System/Game Gear version. "Sonic Chaos"/"Sonic and Tails" (Japan), released in 1993, was similar to the earlier two Sega Master System/Game Gear "Sonic" games, but featured Tails as a playable character. A sequel, "Sonic Triple Trouble"/"Sonic and Tails 2" (Japan), a 2D platform game, was released in 1994 for the Game Gear and introduced a new character, Nack the Weasel, who, along with Knuckles and Doctor Robotnik, raced to collect the Chaos Emeralds. One of the last games for the Sega Game Gear, "Sonic Blast", was released in 1996 and featured prerendered sprites.
Sega Genesis
While Sega was seeking a flagship series to compete with Nintendo's Mario series along with a character to serve as a company mascot, several character designs were submitted as part of a company-wide contest, including "an anime-inspired egg and a teal hedgehog with red shoes created by Naoto Ohshima that he called Mr. Needlemouse." This character won the contest and was renamed Sonic the Hedgehog, spawning one of the best-selling video game franchises in history. The gameplay of "Sonic the Hedgehog" originated with a tech demo created by Yuji Naka, who had developed an algorithm that allowed a sprite to move smoothly on a curve by determining its position with a dot matrix. Naka's original prototype was a platform game that involved a fast-moving character rolling in a ball through a long winding tube, and this concept was subsequently fleshed out with Ohshima's character design and levels conceived by designer Hirokazu Yasuhara. Sonic's blue pigmentation was chosen to match Sega's cobalt blue logo, and his shoes were a concept evolved from a design inspired by Michael Jackson's boots with the addition of the color red, which was inspired by both Santa Claus and the contrast of those colors on Jackson's 1987 album "Bad"; his personality was based on Bill Clinton's "can do" attitude.