Tetsuya Mizuguchi, the man behind Rez, Lumines, and Child of Eden, isn't currently developing games at Q Entertainment. Company director Nobuhiko Shimizu told Eurogamer that Mizuguchi is taking on a "spokesperson" role, having become more involved with "academic work."
Mizuguchi's game development career began at Sega in 1990. There he created Sega Rally, Space Channel 5, and Rez, before moving to Q Entertainment in 2003. At Q he designed Lumines, Ninety-Nine Nights, and most recently Child of Eden. While Mizuguchi didn't oversee Q Entertainment's latest game, Lumines Electric Symphony, he was heavily involved with its development.