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 Heroes
Sonic Heroes is a 2003 3D platform game in Sega's "Sonic the Hedgehog" series. The player races a team of series characters through levels to amass rings, defeat robots, and collect the seven Chaos Emeralds needed to defeat Doctor Eggman. Within each level, the player switches between the team's three characters, who each have unique abilities, to overcome obstacles. "Sonic Heroes" abandons the action-adventure and exploration-based gameplay of its predecessors "Sonic Adventure" (1998) and "Sonic Adventure 2" (2001) and instead returns to the linear style of Sega Genesis-era "Sonic" games.