Having finally found a way home, Hajime and his party head to the final labyrinth—the Frost Caverns. Its frigid depths hold the last ancient magic they need to return to Earth, but upon entering the caverns, a strange presence unsettles the party and splits them up, and they become lost in a maze of ice. Separated from the others, Shizuku is forced to fight a copy of herself. Will she be able to overcome this trial and surpass her limits?