Bone Devil

Appearance

Gaunt and insectile, the Bone Devils of Grizburg resemble skeletal wardens draped in stretched parchment skin. Their spined tails drip venom thick as oil, and their claws scrape sparks when they drag across cavern walls. Their skull-like faces glow with lantern fire, their eyes hollow pits where sulfurous light churns. Chains etched with Infernal runes bind them loosely, dangling like reminders of broken pacts.   ---

Origins

Osyluths stalk the Nine Hells as enforcers, yet those that slither into Grizburg are different. Drawn through breaches carved by the Black Fire War, they seeped into the Whispering Depths and became entangled in Zothra-Khaar’s ruin. Their bones crackle with whispers of infernal law, reshaped by the city’s hunger. Some claim they now serve not archdevils, but Grizburg itself.   ---  

Habitat

Bone Devils are rarely seen above ground, preferring the Depths and sealed vaults beneath Rustwater. They haunt collapsed temples, pacing endlessly around forgotten relics. When they do surface, it is usually at the behest of cults or warlocks, their sulfurous smoke leaving permanent stains on the streets of Greendocks.   ---  

Ecology

They feed not on flesh, but on oaths. Every broken promise is like marrow to them, every whispered betrayal another meal. Their presence breeds paranoia: lovers keep secrets, gangs splinter, Barons watch their allies like prey. Where Bone Devils stalk, trust withers, until only suspicion remains.   ---  

Behavior

They act with bureaucratic cruelty. A Bone Devil never kills without record—every victim is marked, cataloged, and whispered into Infernal ledgers. They toy with prey, whispering offers of obedience and power in exchange for freedom, but always enforce the fine print. To them, every mortal is just another clause waiting to be broken.   ---  

Use by Factions

The Rust Barons despise them yet cannot resist their usefulness. A Bone Devil in service can unravel rival contracts, devour traitors, or guard vaults with absolute loyalty. Cults worship them as emissaries of Hell, weaving chains around their shrines to mimic the devils’ own bindings. More than one Baron’s downfall has been written in ink of blood and Infernal script.   ---  

Cultural Role

To the common folk, they are the “Bone Bailiffs.” Their legends warn that anyone who cheats debt or oath will feel claws at their throat by nightfall. Mothers frighten children with stories of Osyluths dragging oathbreakers into sewers, never to return. Among the superstitious, the rattle of chains in the fog means judgment walks nearby.   ---  

Legends

Old Muckfingers tells of a Bone Devil bound beneath Rustwater’s courthouse, chained in a vault of iron. The Barons supposedly consult it when contracts are disputed, feeding it souls of the guilty. He swears the devil sometimes escapes its cell, stalking alleys at night, only to return before dawn with chains dripping in sulfur.   ---  

Infernal Orders

Even in Grizburg, Bone Devils adhere to the law of Hell. Some enforce relic-guarding duties, others hunt oathbreakers, and some act as messengers for greater fiends. What makes them terrifying is their precision: they do not forget, they do not relent, and they never interpret loosely. Their orders are cages of language, and mortals always lock themselves inside.   ---  

Threats to the City

A Bone Devil unleashed can unravel entire networks of trust. Contracts collapse, guilds fracture, and even the Barons hesitate to strike deals. Their poison halts healing, ensuring wounds fester until victims beg for infernal aid. If a brood ever gathered in Grizburg, the city would not just rot—it would consume itself in paranoia.   ---  

Behavioral Oddities

Some carve Infernal runes into walls wherever they pass, binding the area with curses. Others drag chains behind them, the links glowing faint red, said to be fragments of contracts burned in Hellfire. The strangest speak through corpses, their words rattling from the mouths of oathbreakers they’ve slain.   ---  

Adventuring Hooks

• A Baron hires adventurers to recover a stolen contract guarded by a Bone Devil. • Cultists free an Osyluth beneath Greendocks, and oathbreakers begin vanishing. • A merchant’s pact resurfaces, and the Bone Devil sent to enforce it now stalks the alleys. • Infernal glyphs spread across Rustwater, hinting that multiple Osyluths are gathering.   ---  

Closing Words

Bone Devils embody the cruel spine of Hell: order sharpened into punishment, law twisted into weapon. In Grizburg, their presence is doubly dire—for a city that thrives on contracts, betrayals, and bargains, an Osyluth is more than a monster. It is the reminder that every oath has teeth.  
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