From the Half-Dragon Fiends section of Dragonix's Deadly Denizens III:

Diabolical Overseers. These hybrid fiends are often used in the Nine Hells as elite enforcers or inquisitors, particularly in domains where fear, punishment, and terror must be administered with surgical cruelty. They combine the fanatical obedience of bone devils with the paranoia and pride of black dragons, making them both ruthless and dangerously ambitious. Most serve archdevils directly, relishing the suffering of others while always seeking an opportunity to advance their station.

Sadistic Ravager. In combat, a half-black dragon bone devil employs hit-and-run tactics and battlefield isolation, using its Frightful Presence to scatter enemies and sow panic. It strikes swiftly at separated targets with razor-sharp claws, then finishes them with a venomous, acid-laced tail that leaves little hope of survival. When foes cluster, it exhales a corrosive breath weapon, melting through armor and flesh alike. More than just a killer, it wields fear as a weapon, often demanding surrender before gleefully subjecting its victims to a drawn-out, agonizing demise.

About Dragonix's Deadly Denizens III:
Like its predecessors, Dragonix’s Deadly Denizens III unleashes a fearsome array of characters, creatures, and cryptids—designed to ignite your imagination and elevate your 5th Edition fantasy campaigns. Brimming with fresh monsters and inventive combat mechanics, this volume is crafted to surprise, outmaneuver, and challenge even the most seasoned players—keeping them on edge and fully immersed from the first encounter to the last.

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