Chapter 52

Dunste reaches the hall and offers to relay what the disqualified Edel managed to observe before withdrawing. The gathered mages still cannot judge how dangerous a duplicate of Frieren might be, and Sense, restricted by her duties as proctor, declines to weigh in. Lawine and Kanne soon arrive with the decisive detail: the figure animating the copies is an ancient demon known as Spiegel, a fragile thing hidden in the vault that Frieren's clone shields. Since each duplicate only echoes what its original would do, every quirk and flaw of the real mage is inherited by the copy.

Building on that, Fern stages a quick trade of spells against her teacher and reveals to the others that Frieren's mana sense flickers out for an instant the moment she casts. With a target weakness finally pinned down, the group settles into planning, and Frieren, unexpectedly cheerful, throws herself into the talk.

Dunste arrives first, followed by Lawine and Kanne, each adding to the group's understanding of Spiegel and its duplicates. Methode mends Dunste's wounds with the healing drawn from her Holy Scripture. Lawine identifies the vault's occupant as the demon Spiegel and warns of the door's lethal seal, which can only be undone by the death of its caster.

Fern then exposes the brief lapse in her master's mana detection, and the mages convene a full planning session that mirrors how the old Hero Party once mapped out its fights.

The vault door is held shut by one of the highest binding spells, named Sacrificial Treasury Door Lock Magic, that gives way only at its caster's death; the surrounding walls share that same protection, leaving combat as the lone way through.

Lawine knows about Spiegel because her brother rode with the Continental Magic Association's advance party that once moved against the King's Tomb ruins. A flashback recalls Himmel ordering Eisen to bait a towering monster while Frieren supplied covering fire and a hungover Heiter sat the fight out. Frieren closes the meeting by declaring that no dungeon is ever truly unbeatable, citing the record of the party she ran with.