Bone Devil 5e: Stats and Guide for Players & DMs

Last Updated on November 6, 2023

What Is a Bone Devil in DnD 5e?

A Bone Devil is a type of devil that is found in the Nine Hells. Bone Devils are also known as Osyluths.  Adventurers usually encounter these monsters in the Lower Planes. Bone Devils are physically imposing creatures; they use their strength and power to bully others into submission.

Osyluths are usually found in the company of the archdevils they serve as they make loyal and effective bodyguards.

Bone Devils are also known for their cunning and deceit, which they use to get what they want. 

Intensely envious of their superiors, these creatures are always looking for ways to make themselves look better in the eyes of their masters.

While Bone Devils are usually found in the Lower Planes where they torment the souls of the damned, this isn’t always the case.

 They can also be summoned by evil mortals to do their bidding. You can read about devils and their history in our guide to devils.

Bone Devils in Combat

These creatures usually prefer to attack with their stingers, which can poison their opponents. 

They will also use their claws to slash at their foes and have the ability to fly, which gives them a tactical advantage in combat.

When fighting groups of opponents, Bone Devils usually try to isolate one victim and focus their attacks on that individual. 

Some Bone Devils carry a polearm made of bone, which deals 2d12+4 piercing damage. These polearms have a hook on the end that the Bone Devil uses to grapple opponents. 

When fighting, Bone Devils often try to fly above their opponents and rain down attacks on them from above. Their poison can be deadly if not treated quickly.

How To Summon a Bone Devil

All devils have a true name, which can be used to summon them. However, devils are very reluctant to divulge their true names. 

They will only do so if they are threatened with significant harm. As a rule, Bone Devils hate being summoned and will do everything they can to escape. 

They are also not above betraying those who summoned them. Many mages have met their end by summoning defiant devils. 

Another way to fetch a devil is to open a portal to the Nine Hells and go there yourself. 

This is a dangerous undertaking as the Lower Planes are fraught with danger. Only experienced adventurers should attempt to travel to the Nine Hells as they will likely not make it out alive.

What Are a Bone Devil’s Weaknesses?

Bone Devils are immune to fire and poison and are resistant to cold. They are resistant to most physical attacks as well. 

You’ll need a magic weapon to hurt these devils or a silvered weapon. With a silvered weapon, you’ll be able to do normal damage, but bone evils can fly, so hitting them is difficult. 

They also have a poisonous sting, which can deal severe damage. Silver arrows are a good choice if the party has an archer.

Bone Devils have a resistance to magic, so landing a spell on one is tricky. They are also immune to being poisoned. 

Spells like Lightning Bolt, Inflict Wounds, and Melf’s Acid Arrow can all significantly damage these creatures.

Another way to defeat a Bone Devil is to banish it. A powerful Wizard or Cleric could send a devil back to the Nine Hells, buying the party some time to escape.