Loki Familia's journey to the Dungeon's depths is well under way, but the real trial is just beginning. An attack from dragons far below sends Lefiya plummeting toward the fifty-eighth floor, with half the expedition's party after her. Now floors apart, those separated struggle to hold their ground against the Dragon's Urn while Aiz and the others race to rejoin them.
The promise of answers awaiting on the fifty-ninth floor lures the expedition down deeper than ever before, but no one could have prepared for what lurks in the unknown...When all hope is lost and the finest have fallen, who among them will exceed their limits?!