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.
History of Sega
To compete with Nintendo, Sega was more open to new types of games than its rival, but still tightly controlled the approval process for third-party games and charged high prices for cartridge manufacturing. Technicians from American third-party video game publisher Electronic Arts (EA) reverse engineered the Genesis in 1989, following nearly one year of negotiations with Sega in which EA requested a more liberal licensing agreement than was standard in the industry before releasing its games for the system. As a result, EA signed what founder Trip Hawkins described as "a very unusual and much more enlightened license agreement" with Sega in June 1990: "Among other things, we had the right to make as many titles as we wanted. We could approve our own titles ... the royalty rates were a lot more reasonable. We also had more direct control over manufacturing." The first Genesis version of EA's "John Madden Football" arrived before the end of 1990, and became what EA creative officer Bing Gordon called a "killer app" for the system.