Stronghold made for the liche Haukagaron. He was betrayed at the last and Castle Kaukenn was pulled into the Abyssal realms.
It was said that the King fell from grace so abruptly that the earth opened up beneath his citadel so he could fall for eternity. This is exactly what happened...
Down it falls, a great concentric castle of dark stone. Cracked and broken, though upright, pieces large and small fall together in concert, frequently dashing against each other, or drawing apart to create wide gulfs to expose the hungry blackness below.
And in this tumbling castle, there sits a king, his head heavy with his crown, his hands clutching his throne in unending terror.
100 Word Castle
A handful of tables for randomly generating a colorful history for castles and other fortresses.
The blighted and forgotten hall of a once mighty demon lord
When you sleep, your soul briefly returns to the place where it was created/goes to when it dies, and seeks nourishment. Everybody's soul is created with a little link (or you could say a greater entity calls it back) to that place so that it can return easily, but upon death, the soul returns via that and annihilates the link as if returns.
Also, as an added thingy, you could say the entity supplying the link, or residue of the links themselves, (whichever) is the source of all arcane power.