For the franchise's 15th anniversary in 2006, Sonic Team developed "Sonic Riders", "Sonic the Hedgehog", and a GBA port of the original "Sonic". "Sonic Riders", the first "Sonic" racing game since "Sonic R", was designed to appeal extreme sports fans as well as regular "Sonic" fans. With a more realistic setting than previous entries, "Sonic the Hedgehog"—commonly referred to as "Sonic '06"—was intended to reboot the series for seventh-generation consoles such as the Xbox 360 and PlayStation 3. The development faced serious problems; Naka, the last of the original "Sonic" development team, resigned as head of Sonic Team to form Prope, and the team split so work could begin on a Nintendo Wii "Sonic" game. According to Iizuka, these incidents, coupled with stringent Sega deadlines and an unpolished game engine, forced Sonic Team to rush development. None of the 15th-anniversary "Sonic" games were successful critically, and "Sonic '06" became regarded as the worst game in the series, panned for its bugs, camera, controls, and story. Brian Shea of "Game Informer" wrote that it "synonymous with the struggles the "Sonic the Hedgehog" franchise had faced in recent years. "Sonic ['06" was meant to be a return to the series' roots, but it ended up damning the franchise in the eyes of many."