Sonic the Hedgehog Pocket Adventure
In August 1999, SNK announced that they were collaborating with Sega to develop a "Sonic the Hedgehog" game for their Neo Geo Pocket Color handheld system. The game was developed by SNK, with supervision from Yuji Naka and Sonic Team at Sega. This marked the first time Sega was directly involved in the development of a "Sonic" game for a non-Sega platform. The team planned for "Sonic Pocket Adventure" to be a return to the classic 2D gameplay style found in the "Sonic" games on the Sega Genesis. In particular, many game design and visual elements are borrowed from "Sonic 2". The game's background music tracks are also 8-bit renditions of music from "Sonic 3". "Sonic Pocket Adventure" was released first in North America on December 4, 1999. SNK released a system bundle with the game included for the holiday season. The game was released in Japan two weeks later, and in Europe in February 2000.
Sonic the Hedgehog (TV series)
Several video games were intended to use elements from the TV series, although only one was completed. This was "Sonic Spinball", released in 1993 for the Sega Genesis. It contained characters from the show, including Princess Sally, Bunnie Rabbot, Rotor and Muttski. The characters were also planned for use in another game, tentatively titled "Sonic-16". A prototype was created by the Sega Technical Institute. Yuji Naka disliked the project, and it was cancelled without further development. Directly afterwards, the same team worked on "Sonic Mars". Prior to cancellation, this would have featured Princess Sally and Bunnie Rabbot as playable characters.