Yuuto Suoh, a young man who was transported to the world of Yggdrasil and became the patriarch of the Wolf Clan, leads his people into war with the Horn Clan alongside one of his Einherjars, Felicia. Using phalanx formations, which Yuuto knows about due to his knowledge of the 21st century, the Wolf Clan overpowers the Horn Clan. The battle ends in the Wolf Clan's victory when another of their Einherjars, Sigrun, captures the Horn Clan's patriarch, Linnea...