A number of "Sonic" games were developed for Sega's 8-bit consoles, the Master System and the handheld Game Gear. The first, an 8-bit version of the original "Sonic", was developed by Ancient to promote the Game Gear and released in December 1991. Aspect Co. developed most of the subsequent 8-bit "Sonic" games, beginning with a version of "Sonic 2". Other "Sonic" games released during this period include "Dr. Robotnik's Mean Bean Machine" (a Western localization of the Japanese puzzle game "Puyo Puyo"), "SegaSonic the Hedgehog" (an arcade game), and "Knuckles' Chaotix" (a spin-off for the Genesis's 32X add-on starring Knuckles).