Demons are demons, right? Monsters from Hell, the Abyss, or whatever else you want to call it. What more is there to know? Well, the lore of D&D has demons operating differently than most other depictions of demons in the fantasy world, and in this DnD demons guide, we are going to break them down. This will probably change how you look at these creatures going forward, so be prepared for a mind shift!
What Are Demons?
This is actually a tricky question to answer, because of the lore. For starters all demons and devils are fiends, and demons and devils are not the same things. In fact, they are vastly different and hate one another. There are three main categories of demons, with the first being the obyriths.
The obyriths are the oldest of the demonic raises, and they had ruled the abyss for years. They also created the tanar’ri, the second race of demons, and they were subsequently defeated by slave rebellions and sent into hiding. The obyriths were almost eldritch in nature, and they predated mortal races and even the gods themselves. Some even think they came from another reality altogether.
The tanar’ri are the demons that we see today. They rule the Abyss in modern times and were created when evil human souls entered the Abyss. The tanar’ri are dominant and are souls that have been infected with chaos. They are vice personified, and various demonic creatures and lords are tanar’ri. These include vrocks, marliths, balors, and even the demon lord Demogorgon.
These demons are bred for evil and destruction, and they have no friends, no allies, and no remorse for anything they do. Typically, if you are fighting demons in the abyss, then you are fighting some type of tanar’ri.
Finally, the Loumara are the youngest race and are typically immaterial beings that seek to possess and cause harm. Most of them are said to be from the dreams of dead gods, and they seek to spread evil however they can.
Other Demon Types
Of course, there is all manner of horrors roaming the Abyss. Demonic constructs, living demons and monsters specifically created by demon lords, demons so savage and mindless they might be considered wildlife, and others that can’t even be put into a category. And those are just the ones that are official! It says nothing about the various homebrewed and other 3rd party horrors DMs can place in their worlds!
Not everything with demons is killed or be killed, however, as some demons rose up and became demon princes or lords. The demon lords commanded armies of followers and often battled against devils and their own kind for the right to be the only demon prince left standing. Typically, if your party is fighting a named demon, then they are crossing blades with a demon prince.
What Are Devils Then?
It’s hard to believe that something Lawful evil can exist in the Underdark, but it can! These devils are more like fallen angels in their mannerisms, and rather than being mindless fighters they are tricksters and liars. Rather than kill a human and take his soul, they want to trick you into giving it away through a contract. Devils also have a strict hierarchy in their lands.
Unlike with demons where every powerful demon with an army can just up and call himself a demon prince, every devil is subservient to another devil and they know this, all the way up to archdevils and then the highest devil ever: Asmodeus. Every devil has a purpose, and they seek to serve it well. Heck, devils even follow the rules set out in their contracts. They know all the loopholes, stack the deck, and take advantage of every bit of ambiguity that they can find, but if someone manages to beat or outwit them, they follow the contract and take the loss.
The Blood War
Given the sheer chaoticness of the demons and the lawful order of the devils living in the abyss, the conflict between the two seems like a no-brainer. This leads to the Blood War. No one really knows what started the Blood War, but the very violent nature of the demons and devils has seen it continue for literally millions of years.
Most of the time the battles are centered around the 1st of the nine layers of hell, Avernus. This place is the Abyss, and demons invade downward while Devils push upward, fighting in bloody clashes to gain territory that could be lost to them tomorrow. Now, this Blood War seems like a good thing, right? As long as the forces of evil are ripping each other apart, then they can’t attack the surface world.
Well, sometimes cults devoted to one side or the other will attempt to curry favor or find secrets to aid their side in winning the war. When this happens, sometimes the war spills out of Hell and into the mortal world. This causes frequent devastation and death as both sides class, not caring about the mortals caught in their way.
Plus, the Blood War can never truly end. Both sides are continuously gaining reinforcements because it is notoriously hard to kill a demon or devil if you aren’t on their home plane. The continuing Blood War is often called ‘The Balance’ because if the scale tips too far in one side’s favor and the war ends, the mortal races and the other realms of goodwill pay the price.
Whichever side remains will be able to invade whichever realm they choose unopposed, and no one wants that to happen. Thankfully, the war seems to be going on nonstop at the moment, and it will likely continue this way.
How To Fight A Demon
Whether you are in the Abyss or the mortal world, fighting demons can be a tough battle. Depending on which type of demon you are fighting, you might need to change up your tactics, but here are a few basic tips.
First, avoid magic. Most demons have spell resistance, and if they are on fire they probably have fire resistance or immunity too. Spellcasters hit these demons with the most powerful spells you have, but don’t expect them to do much. Instead, focus on buffing your party instead.
Second, many demons have multi-attack, which means you need to have as many frontline fighters engage the enemy as possible. This way the demon needs to either spread out their attacks and deal less damage or lay the hurt on one party member but risk that the others will attack it.
Also make sure your fighters are armed with holy weapons, cold iron, or some other magical weapon to deal as much damage as possible. Most demons have high damage resistance, and you want to counter that. Finally, keep healing. Most of the stronger demons will out damage you, so having someone who can spam healing spells is what you need.
Finally, know that this is not a battle to the death, it’s a fight to the wound. Even though most demons will simply wind back up in their home plane if they die, they don’t like dying, and many of them will simply try to escape if necessary. If you can hurt it enough, it can flee. It will later come back with a vengeance, but it will flee the first time.
How Do Demons Attack The Mortal World?
Since most demons and devils are denizens of the abyss, you might wonder how they actually get up to our surface world and attack. Well, often they are summoned by powerful spellcasters and necromancers who are worshiping a demon prince or other named demon for their power or perhaps even trying to gain control over the demon.
Other times magic can cause portals or gates to open, and demons just come pouring out. They start attacking because that is their nature, and they start ripping through anything in their way. Sometimes, although this is exceedingly rare due to their needing to be on the battlefields of the Blood War, sometimes demon lords will lead an army to the surface or to the Underdark, launching a campaign of mayhem and destruction.
And clever DM’s can homebrew other ways to get the Blood War from under the mortal world to atop it, and really raise the stakes for players! Those are going to be some really interesting adventures.
DnD Demons FAQs
Question: What Are Some Common Demons?
Answer: Common demons can be whatever the DM wants them to be, but if we are sticking to official content there are several demons most adventurers encounter with some regularity. These are all from the monster manual.
• Dretch, which are the lowest of the low and normally use their great numbers to overpower foes. They do have a special attack: Fetid Cloud (1/Day). A 10-foot radius of disgusting green gas extends out from the dretch. Any creature that starts its turn in that area must succeed on a DC 11 Constitution saving throw or be poisoned until the start of its next turn.
• Maralith’s: Giant 4 armed snake women who use swords and overcome their foes with a flurry of blows (They can make 7 attacks with their longswords and tail, one of those is gonna hit!). They also can parry your blows as a reaction: Parry The marilith adds 5 to its AC against one melee attack that would hit it. To do so, the marilith must see the attacker and be wielding a melee weapon.
• Balors are probably the most recognizable demons in 5e, armed with flaming whips, flaming swords, and fire! Also, they explode when they die!: Death Throes When the balor dies, it explodes, and each creature within 30 feet of it must make a DC 20 Dexterity saving throw, taking 70 (20d6) fire damage on a failed save, or half as much damage on a successful one.
These demons might be “common”, but your players will wish they weren’t dealing with them if they aren’t prepared!
Question: What Adventures Have You Facing Demons?
Answer: Disregarding homebrew adventures and other 3rd party content, two adventures have you facing demons.
• Out Of The Abyss has plenty of demonic influence throughout the first half as the players are escaping the Drow prison and making their way through the Underdark. Including an encounter with Demogorgon himself! The second half has the player and their allies taking part in an invasion of the Underdark to fight the demonic princes themselves.
• Descent Into Avernus has the players dealing with a cult at Baldur’s Gate and eventually needing to find a magical sword that belonged to an angel seeking to end the Blood War. This takes the party down to the first layer of Hell, complete with Mad-Max-style death machines, political intrigue, and some of the biggest and bloodiest battles of the Blood War.
Of course, there are more official adventures that have you facing demons and devils alike, but those two stories have demons, the various demon princes, devils, and the Blood War as the main characters and background events. Plus, they are both very fun to play with at a dedicated party!
Question: Can Demons Be Banished?
Answer: If you are stuck in a fight you can’t win and know that the demon you are fighting will not leave of its own volition, then your spellcaster might be tempted to end the fight early and cast banish. Since the mortal world is not the demon’s own plane of existence, you can attempt to banish them.
The spell will succeed without any checks or saving throws by the demon and they will not return so long as you can keep the spell up for one minute (10 combat rounds). Make sure to avoid getting hit or anything that could damage your concentration, and then the demon will not return. Well, they might come back, and chances are they will target the spellcaster first to make sure that same trick can’t be pulled again!