The king of Kobalos is no more, but the new ruler and the nation still must pick up the pieces. To this end, Sergeant Lerebus Shieldbreaker leads a squad into the depths of the city's dungeons in order to clear out rumored monsters and to negate magical wards laid down by the old king. However, Lerebus soon finds more than monsters and magic below the castle of Mogus Potere. An old enemy appears once more, an enemy against whom Lerebus has few defenses, and this enemy calls upon Shieldbreaker to perform a task no other could accomplish.