The narrative takes place in the near future. Five "Black Points" suddenly materialize globally, serving as gateways to parallel dimensions. Right away, bizarre entities launch an invasion through these portals. These beings originate from five distinct worlds—variations of the same world across different timelines. To guarantee the survival of their respective future eras, each of the five invading factions fights to eradicate the other future timelines. The crucial element is a single card-shaped device.