Some were disappointed by the absence of the "Streets of Rage" games in the International version and other "Sonic" games like "Knuckles' Chaotix" and "Sonic the Hedgehog Pocket Adventure". "Sonic Gems Collection" is a compilation of obscure video games published by Sega for various consoles, such as the Sega CD, Sega Saturn, and Game Gear. It primarily focuses on "Sonic the Hedgehog" games, such as "Sonic CD" (1993) and "Sonic the Fighters" (1996). It also includes six of the twelve "Sonic" games released for the Game Gear. These games encompass various genres, such as platforming, fighting, pinball, and puzzle. Additionally, players can unlock several Sega Genesis games unrelated to "Sonic", including the two "Vectorman" games (1995 and 1996). Four games in the japanese version, "Bonanza Bros." (1990) and the "Streets of Rage" trilogy (1991—1994), are not included in the international version. Each game is mostly identical to its initial release, but some were changed; for example, "Sonic R" runs at a higher frame rate. The compilation features an extensive museum section in which players can view content—such as promotional artwork, videos, screenshots, and music—unlocked after obtaining achievements. Time-limited demos of the original Genesis "Sonic" games and the other six Game Gear games can also be unlocked. In each demo the player begins in the respective game's final level and can play until the time limit is met. "Sonic Gems Collection" was developed by Sonic Team and published by Sega for the GameCube and PlayStation 2. According to Sonic Team director Yojiro Ogawa, the compilation (and its 2002 predecessor "Sonic Mega Collection") was conceived to introduce young players to older games in the "Sonic" franchise. While "Sonic Mega Collection" focused on the original Genesis games to showcase what made the franchise a success, "Sonic Gems Collection" focused on games Sega considered rare and obscure. Although Sonic Team was responsible for "Sonic Gems Collection"s creation, they had limited involvement in the development of the games included on the compilation; for example, Sega AM2 made "Sonic the Fighters", and "Sonic R" was primarily developed by Traveller's Tales. Most of the games included are emulated, but "Sonic the Fighters" is a port. At the beginning of "Gems Collection"s development, Sonic Team made a list of the most wanted games for the compilation.