Xar-Azmak was living entropy. He roamed the planes to corrupt all he found with his touch and aura: metals, stone, flesh, and hope.
After destroying a large portion of Dis which is still in ruins, Xar-Azmak was destroyed by Dispater's forces.
Like all dead demon lords, Xar-Azmak's quasi-soul now resides in the Abyssal Rift of Repose, though he originally ruled his own Abyssal realm of Vlorus.
Xar-Azmak appeared in the form of a rusted iron golem with horns and hooves.