While retracing the path she took on her adventure with her former traveling companions, Frieren confronts an old enemy.

Due to the Spiegel, a legendary monster that can create perfect replicas of others, the test-takers who would conquer the Ruins of the King's Tomb must first face the ultimate enemy: themselves.

To defeat Spiegel, Frieren and Fern fight against Frieren's replica, but have a tough time. Meanwhile, Denken, Lavine, and the others fight against the replicas, but the magic of Sense, a first-class mage and the exam's proctor, rages.