Magedoom and the Demiliches

After a hundred years of dregloth decline, auroc and bazlogh, the Demilich Twins of Cinspire, re-united the scattered remnants of the Legion of Bone and marched on Magedoom.
Magedoom used the scores of red cloaks —the arcane diaspora of wizards populating the Empress' cities— to convince her to ally against the Twins.
however, When the demiliches sieged Magedoom, the Empress reneged on her alliance, rounding up and executing hundreds of the former summoners and leaving Magedoom to its own devices.
The evening before the final destructive push, one of the Twins, Auroc, decided to stop pursuing worthless material gains and disappeared to walk the planes in search of some unknown knowledge. His brother Bazlogh disappeared without a trace exactly one day afterward, and the last true Dregloth threat sank into history.