This is the fourth as well as the final game of the Gensou Shoujou Taisen series. The fourth part retells the story of Undefined Fantastic Object (Touhou 12), Mystic Square (Touhou 5), and an original arc loosely based on Yumetagae Kagaku Seiki - Changeability of Strange Dream, a doujin album by Team Shanghai Alice which was released on 2004.