Legends about Excalibur, a legendary sword, have been passed down through the ages. The sword is wielded by individuals deserving of its power, imparting exceptional strength and conferring the title of Arthur onto them. A heavenly miracle, however, causes the production of many Excaliburs, disrupting the fabric of time. A party of six Arthurs comprised of Danchou, Renkin, Kakka, Yamaneko, Tekken, and Rurou are sent back in time after the anomalous Excaliburs were produced in order to reset time to its original course. They have been tasked with destroying the Excaliburs of the past, a total of one million in all.