Dax Doomslayer
Adventurer
My 'google-fu' comes up with this:This is maybe an unreasonable piggybacking, but does anyone know if there is an adventure associated with this fun little map in the 2014 DMG?
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Vault of Catharandamus
The dungeon on pages 276-281 in the "Tome of Magic: Pact, shadow, and truename magic supplement" (2006) by Matthew Sernett et al. for 3.5e is the "Vault of Catharandamus".

The "Vault of Catharandamus". Cartography by Mike Schley.
The location is described as a truename magic adventure site:
A few crumbling walls, eroded statues and columns, and the remnants of a few roads are all that remain of the Palace of Princess Argent. Years ago, a foul and alien sorcerer named Arik imprisoned the lady and her beloved champion beyond time and space, and cursed the place. Serving the dark spellcaster was a despicable man named Catharandamus who worked to bring his master into the Material Plane. Though a group of bold adventurers thwarted the curse, freed the princess and her knight, and put an end to the spellcaster’s evil, the palace never recovered, nor did the lands around it. Over the decades since, earthquakes, rains, and time took their toll, leaving little but a pile of rubble and a passage into a hill on which the palace once stood as evidence that anything ever stood here.
from the "Tome of Magic" (2006)