Karl focused on the interior of the Dark Elf city, the mushrooms, the glowing fungus, the crystals, and finally the dark black angular buildings. One by one, he described every element of the city as they had encountered it, with the beasts filling in any gaps they thought were important.
For example, Thor insisted that it was important they note that the short glowing grass smelled like mint, and Rae noted that the black buildings had been painted with blood in the past, but the stone itself was black, so you couldn't see it.
Both of those were good points, and they helped Morgana narrow down the era and region that they had seen replicated in the dungeon, even though the Dark Elves made it fairly obvious who had built the city.
When he got to the man standing on the platform, preaching about the dungeon being opened for the people of the city, and more specifically his outfit, Morgana knew exactly when and where Karl had been sent to.
