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 Gems Collection
Developer Sonic Team conceived the compilation to introduce younger players to older "Sonic" games. One game they wished to include, "SegaSonic the Hedgehog", was excluded due to emulation difficulties. Sega released "Gems Collection" for the GameCube and PlayStation 2 in August 2005. Reviews were mixed or average; critics were divided over whether the package would satisfy players. They preferred "Sonic CD" and "Vectorman", but found "Sonic the Fighters" and "Sonic R" mediocre, and disliked the Game Gear games. Some were disappointed by the absence of the "Streets of Rage" games in the American version and other "Sonic" games like "Knuckles' Chaotix" and "Sonic the Hedgehog Pocket Adventure".