The Houses of Cadyr Tzithes

More than a thousand years ago, the demon prince Shazramatix gained entry to the mortal plane, and in his wake thousands of fiends followed. Spawned from a portal deep in the underdark where his Duergar priests foolishly summoned him -- and perished with his emergence -- the infernal forces threatened to overrun the surface world. The surface dwellers above were already engaged in widespread warfare with one another when the demons began their rampage, but the various magical institutions across the continent set aside their national interests, and allied to drive the fiends back. Ultimately, they were successful, but could not completely banish Shazramatix. Instead they imprisoned him in the Godstomb, a powerful artifact of their own construction, devised for this very purpose. Yet it proved insufficient to contain the demon prince by its own power, and required the constant will of some of the world's most powerful mages to maintain. While the alliance still lasted, they formed the floating fortresses which would come to be known as the Houses of Cadyr Tzithes, whose name derived from an ancient tongue and meant "We Too Are Prisoners."

In each of the floating fortresses reside the once-mortal archmagi who defeated Shazramatix. They each assumed a form of undeath similar to lichdom to oversee the eternal burden of containing the demon. The immense magical power required to do so cannot be sustained by any individual, or even a group, in perpetuity. The twin fortresses exist to relieve one another of this great burden, taking shifts and exchanging places over the Godstomb every ten days. This cycle has gone undisturbed for over a thousand years.

The path through the underdark to the immense cavern where dwells the Godstomb and the Houses of Cadyr Tzithes is relatively easy to find and follow. However, neither surface dweller nor underdark denizen is foolish enough to approach two dozen liches and their demon prince prisoner. Yet a few who have dared to spy it from a distance describe a curious microbiome leading to the floating Houses, where trees, grass and flowers from the surface thrive. Some speculate this too is the work of the liches, who have created a memory of the surface to make their existence bearable. - Nevvur