The eponymous first game in the series was released in 2003 on the PlayStation 2, and has since been followed by a sequel, a prequel, and a spin-off. It was conceived by Takamasa Shiba and Takuya Iwasaki as a gameplay hybrid between Ace Combat and Dynasty Warriors 2. The story was created by Shiba, Iwasaki, Yoko Taro and Sawako Natori, who were influenced by European folklore and popular anime series and movies of the day.