Aurnozci

Aurnozci
The demon lord Aurnozci is a wormlike horror of fiery flesh and toxic seepage. In its present form, Aurnozci can't leave Xulregg, the Abyssal layer that's both its fiefdom and its prison. It lairs within a grotesque hive dangling from a mountain-size tree of tar and flame called Gorewood.
Aurnozci relies on demonic proxies and mortal worshipers to enact its will beyond the Abyss. The exact nature of the curse that binds Aurnozci to Xulregg is its cult's most closely guarded secret, fully known only to the faith's enigmatic leader, a masked archmage called the Eye of Aurnozci.
Aurnozci's followers believe the demon lord's imprisonment is coming to an end, and soon the Caged Worm will shed its current form and transform into an even more powerful shape. Once it attains this new form, Aurnozci can escape Xulregg and wreak havoc across the multiverse. To accelerate this terrible transformation, cultists hunt down mortal souls for violent ritual sacrifice to their god.
Cultists of Aurnozci
Aurnozci grants its cultists the following trait:
Burning Corpse
When the creature dies, its body is reduced to a pile of smoldering embers in the space where it fell. The ashes take 1 minute to cool. Until then, a creature takes 3 (1d6) fire damage when it enters the ashes' space for the first time on a turn or starts its turn there.
Aurnozci's Lair
Aurnozci's lair is a layer of the Abyss called Xulregg. See chapter 20 for details about this realm.
The challenge rating of Aurnozci is 23 (50,000 XP) when it's encountered in its lair.