List of Sonic Team games
In addition to the "Sonic" series, the company has developed other games for Sega, such as "Nights into Dreams" (1996) and "Billy Hatcher and the Giant Egg" (2003). The 1991 release of "Sonic the Hedgehog" is considered significant in video game history, as it increased the Sega Genesis's sales and Sega displaced Nintendo as the leading video game company. Some of Sonic Team's games, such as the Genesis-era "Sonic" games and "Nights", are considered by critics to be among the greatest video games ever released.
Retro Engine
Christian Whitehead first created the Retro Engine for use with a 2007 fangame entitled "Retro Sonic", which is based upon the original "Sonic" games released for the Sega Genesis. The game became notable after its release for its accuracy to the games, despite not being a ROM hack or modification to an existing "Sonic" game. "Retro Sonic" later merged with two other "Sonic" fangames, "Sonic XG" and "Sonic Nexus", to form "Retro Sonic Nexus".