After finishing his work on
Romancing SaGa 2, Matsui joined the development of
Chrono Trigger midway through. He was responsible for planning and the movements of monsters in battles. Since 2000, Matsui has been a member of the production staff for the
MMORPG Final Fantasy XI, where he was in charge of the battle system. He became the director of the game's ongoing development in September 2010 but was succeeded by Mizuki Ito two months later. Matsui was switched to the
Final Fantasy XIV team as lead combat system designer following the game's unsuccessful launch. When
Final Fantasy XI producer
Hiromichi Tanaka left the company in August 2012, Matsui was chosen to fill the position in his place. In March 2023, Yoji Fujito replaced Matsui, who would in some form continue supporting
Final Fantasy XI. ==Works==