Kawazu's first job at Square (later Square Enix) was as a graphic designer for "Rad Racer". Following that, he was asked by Sakaguchi to make the company's new role-playing game (RPG) project "Final Fantasy", begun by Sakaguchi after the genre was proven as commercial viable by Enix's "Dragon Quest". At the time, Kawazu had no idea how popular the title would become; his role was designing the battle system. He returned as battle designer for its sequel "Final Fantasy II". As part of a drive to create something different from the original, he created a notorious system of use-based statistic gains. In the wake of internal discussions and a lack of outside understanding of Kawazu's systems for "Final Fantasy II", future titles beginning with "Final Fantasy III" went back to the basic systems of the first game.