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 Blast
The game was developed by Aspect Co. and published by Sega for the Game Gear. It was the final "Sonic the Hedgehog" game for the system, and has been rereleased on the Master System (1997), through two "Sonic"-themed compilations (2003 and 2004), and the Nintendo 3DS's Virtual Console (2012). Despite their similar titles and coinciding releases, "Sonic Blast" and "Sonic 3D Blast" have little in common. Retrospective reviewers generally had little praise for "Sonic Blast" and have deemed it one of the series' worst games. Although some considered its graphics impressive when considering the technological restrictions of the Game Gear, most found its animations and colors mediocre. The level designs and slow gameplay were also criticized.