Sonic the Hedgehog 2 is a side-scrolling platform video game developed by Aspect and released by Sega for their Sega Master System and Game Gear formats. The Master System version was released in Europe on October 25, 1992, and in Brazil around the same time. The Game Gear version was released in Europe on October 29, 1992, in North America on November 17, 1992 and in Japan on November 21, 1992. Being released before the 16-bit version for the Mega Drive (Genesis), the 8-bit editions of Sonic the Hedgehog 2 represent the debut of character Miles "Tails" Prower, Sonic the Hedgehog's best friend who became a recurring character in the series.