Killorn Keep

Atarka is the non-canonical name for a world the Avatar visits in Ultima Underworld II: Labyrinth of Worlds. The Avatar only visits two locations, Killorn Keep and the Tomb of Praecor Loth, though he hears of others.

Atarka is a world on a parallel plane from Britannia, and has already been conquered by the Guardian. He rules Killorn Keep through a puppet king, Lord Thibris, and eight virtues of his own.

Atarka's name was originally generated by Shadow of Light Dragon for her Ultima fanfiction "The Black Ankh", and the name has since been widely accepted by fans of the Ultima series.

Killorn Keep
Killorn Keep is, where Lord Thibris presides as a reward for killing Praecor Loth. It is a flying castle a mile over the great desert of Atarka. The Avatar is told that it is used to intimidate the nomadic, babarian people of the desert. The Guardian's magic holds the keep in the air, through it can be disrupted, resulting in the keep crashing. Killorn Keep is not the central power of its world, as many see it as a backwater and consider being trasferred there as some kind of penalty.

Tomb of Praecor Loth
As told by Lord Thibris, Praecor Loth was defeated in a war 700 years ago (meaning that he is REALLY old, like Lord British). This also means that the tomb is on the same world as Killorn Keep. His tomb is build into a cliffside far in the north, and very well trapped, making it impossible to loot it, despite the Guardian's best tries. The dead aren't dead in this place and the Avatar has to solve the problem, to give them their final peace.