Архибестия

Source War of Immortals
Fiends are legion. From the scheming, tyrannical devils and the sinful, soul-coveting demons, to the terrifying sahkils and the unknowable qlippoth, they come in countless forms and are more numerous than the stars in the sky, the sands upon the beach, and the sins of morals. Beings of cruelty and malice, cunning and corruption, fiends revel in bloodshed, violence, and destruction. These are the forces you're destined to join and eventually rule over—the servants and soldiers who will protect your domain, carry out your orders, and destroy your enemies.
Through your Calling, you're destined to become an archfiend, a powerful leader, general, or tyrant who rules over your own extraplanar realm and amasses a following of fiends. A devious archdevil who rises through the ranks of Hell's hierarchy, a powerful demon lord who seizes their realm in the Outer Rifts by bloody coup, a fearmongering sahk il tormentor who builds a palace of nightmares in their own personal demiplane, and a sadistic velstrac demagogue who cuts a swath of agony through the Netherworld—all are archfiends. And while their motives, methods, domains, and minions differ, the evil they cause and the power they wield are universal. Archfiends are fiends of legend, whose names live on forever, both among their own kind and the mortals who fear them. The most powerful of archfiends gain a horde of fiendish followers who help them bring evil to the mortal realms.
Moloch (tyrannical male devil general), General of Hell, rules Malebolge and directs Hell's armies from Melqart Keep at the heart of Citadel Ba'al. The Lord of the Sixth personifies wrathful destruction held in check by absolute discipline, and those who honor him often find their enemies crushed by the might of his armies.
Scheming in his twisted tree lair known as the Witchbole, the Lord of the Blasted Tarn, Treerazer (corrupting male demon deforester), seeks dominion over the Tanglebriar. Once a powerful aspiring demon lord, the fiend was banished to the Universe long ago and seeks revenge against the elven deities who imprisoned him within the surrounding forest and all they hold dear.
Searching for the perfect beings so she can end all others, Raetorgash (cruel female velstrac demagogue), the Skull-Hoarder, resides in a bone tower at the heart of the charnel house Targothieh with the Netherworld. She often judges potential subjects by the shape and composition of their skulls, usually by first having them removed from the containing skin and muscle.
You wish to number among these mythic beings. You have been gathering power, whether through the study of occult tomes, the accumulation of wealth, or the manipulation of heedless pawns in political spheres. You hold little regard for much of anything except your own goals, though you might briefly ally yourself with others for mutual protection or financial gain. However, should the need arise, you are prepared to abandon those ties without so much as a second thought. After all, you are destined to sit upon a throne that has room for only one —and that is you. The time has come for you to establish your realm, amass your fiendish hordes, and carve your own legend into the annals of history.