The Sea Horse on which Guts and his men boarded has docked in the lair of a malevolent 'sea god'! Apart from a young girl named Isma, the inhabitants of this desolate island have become tentacles of the god, and it is in this sinister form that they attack Guts's troop. Having revealed his true face, the sea god, Guts guessed that he and his companions could not leave the island. In order to eliminate the enemy and without caring about the suffering he will endure once again, he dons the Berserker Armor. But despite its power, this decisive duel turns into a fight to the death!