Keiji Inafune
First developed by Keiji Inafune when he was attempting to create a new design for the "X" series, Zero was instead used as a secondary character. In the "Zero" series (developed by Inti Creates), Zero was the protagonist and had a change in his design that was meant to impart a more "human feel" to him. Zero has since also played a minor role in the "ZX" series as Model Z.