Team launched the role-playing game Phantasy Star Online to critical and commercial success. Sega began to restructure its studios in October 2000 and spun off its software divisions into subsidiary companies. When the departments took new names, Naka felt it important to preserve the Sonic Team brand name, and the division's new legal name as a company was SONICTEAM, Ltd. Naka was installed as the CEO, and Sonic Team USA became a subsidiary of the new company. Despite a number of well-received games, Sega discontinued the Dreamcast in 2001 and exited the hardware business. Sega transitioned into a third-party developer and began developing games for multiple platforms. From 2000, Sonic Team in Japan began to release fewer games, with a few releases such as the puzzle game Puyo Pop and the action game Billy Hatcher and the Giant Egg. The company changes and lack of a Sega console affected Sonic Team; according to Naka, in a 2006 interview, "Our approach was always to create strategic title concepts, which included the hardware. We do somewhat miss the idea of being able to address these constant challenges." However, originality remained important for Naka; Sonic Team developed Sonic Heroes instead of Sonic Adventure 3, explored the digital card game genre with Phantasy Star Online Episode III: C.A.R.D Battle, and developed the original game Billy Hatcher. Naka credited the enduring success of Sonic to the character's appeal to children. Naka's goal was to appeal to the largest audience possible and to appeal to children. Early in 2003, Sega president Hideki Sato and COO Tetsu Kamaya announced they were stepping down from their roles, with Sato being replaced by Hisao Oguchi, the head of Hitmaker. As part of Oguchi's restructuring plan, he announced his intention to consolidate Sega's studios into "four or five core operations". Sonic Team was financially solvent and absorbed United Game Artists, another Sega subsidiary led by Tetsuya Mizuguchi and known for the music games Space Channel 5 (1999) and Rez (2001). 2004–present: Reintegration and recent years In 2004, the Japanese company Sammy acquired a controlling interest in Sega and formed Sega Sammy Corporation. Prior to the merger, Sega began the process of re-integrating its subsidiaries into the main company. Sonic Team USA became Sega Studios USA, while SONICTEAM Ltd. became Sega's Global Entertainment 1 research and development division (GE1). The team is still referred to as Sonic Team. As of 2005,