Sega Genesis
Sega sold 30.75 million Genesis units worldwide. Of these, 3.58 million were sold in Japan, and sales in Europe and the U.S. are roughly estimated at 8 million and 18–18.5 million as of June 1997 (at which time Sega was no longer manufacturing the system) respectively. In 1998, Sega licensed the Genesis to Majesco Entertainment in North America so it could re-release the console. Majesco began reselling millions of formerly unsold cartridges at a budget price, together with 150,000 units of the second model of the Genesis. It released the Sega Genesis 3, projecting to sell 1.5 million units of the console by the end of 1998. An estimated 3 million Genesis units were sold by Tec Toy in Brazil.
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.