You demons. You think you're something special, but you're just spirits -- twisted, perverted, evil spirits, but end of the day, you're nothing but ghosts with an ego.
Demons are malevolent spirits created by Lucifer. They are created from corrupted humansouls after extensive torture in Hell by Alastair and other demons. They become corrupted and extremely evil, and also very powerful, in this process. The species as a whole functions as the series' primary antagonists and are the most recurring creatures in the series. Similar to Angels, they require a Vessel to walk the earth, though are able to roam in their smoke form.
“
My soul did a stint in Hell, where it became demonized. Then I had to possess another person so I could traffic with the living.
It might take centuries, but sooner or later hell will burn away your humanity. Every hell-bound soul, every one turns into something else. Turns you into us.
Although an ordinary demon is featured as a villain of the week in the fourth episode of the series, "Phantom Traveler", demons do not become actively involved in the show until the introduction of Azazel's "daughter"—possessing a girl named Meg Masters—in the second half of the season. She follows Sam and Dean Winchester, and later unsuccessfully sets a trap for them using their father. Following the release of hundreds of demons from the Devil's Gate at the end of Season 2, demons become the greatest, most common enemies the Winchester Brothers face in the series. At the same time, Dean Winchester kills Azazel with the Colt, creating a power vacuum.
An old book depicting a demon.
Due to Azazel's death, the demons are initially disorganized and unable to execute their master plan. Some demons want Sam to lead them, while others follow Lilith. By the beginning of Season 4, however, Lilith has taken control of most of the demons and directs them to break the 66 Seals needed to free Lucifer. Under her direction, the Seals are broken, and Lilith allows Sam to kill her, thus breaking the Final Seal and setting Lucifer free. Throughout Season 5, Lucifer has command over nearly all demons. Dozens sacrifice themselves to assist him in raising Death. Others serve the Horsemen Pestilence and Famine, as well as the Whore of Babylon. Eventually, Lucifer is defeated and banished back to Hell.
In Season 6, in the aftermath of Lucifer's re-imprisonment, most demons have fallen under the command of Crowley, the current King of Hell. However, some demons, such as Meg, oppose his rule. Throughout Season 6, Crowley and his demons secretly assist Castiel in finding a way to open the doors to Purgatory in order to gain access to the millions of monsterssouls inside. They succeed but Castiel betrays Crowley and absorbs all the souls for himself.
During the course of Season 7, the demons take a backseat to the Leviathans as the series' main antagonists. Under Crowley's orders, the demons refrain from attacking the Winchesters, so that the boys can defeat the Leviathans though the Winchesters come into conflict with rogue demons and ones hunting Castiel. However, with the death of the Leviathan leader Dick Roman at the end of the season, the demons are now poised to return to their original role as enemies of the Winchesters, having aided in finishing the last of the Leviathans on Earth.
At the start of Season 8, the Winchesters learn of a second tablet that holds the key to banishing all demons from Earth and closing the Gates of Hell forever. Their quest puts them in direct conflict with Crowley. Through the season, Sam and Dean come into conflict with the demons multiple times over Crowley's various goals. Eventually, after the Winchesters complete the first two of three trials needed to seal the Gates, Crowley keeps demons away from them to keep them from being used in the trial, but Sam and Dean capture him to cure him as the third trial. Crowley starts to become human, but Sam is convinced by Dean to stop after he learns from Naomi that Sam will die if he completes the trials. During the season, the Winchesters occasional enemy/ally Meg is killed. The demon Abaddon arrives in 2013 from 1958 and is defeated by Sam and Dean, but not killed. She eventually escapes after the Winchesters try to use her as the third trial and starts opposing Crowley's rule, wanting a "regime change." Sam manages to defeat her when she tries to kill Crowley, but she merely flees her vessel after it is set on fire with Holy Oil and is not killed.
In Season 9, Crowley is held captive by the Winchesters at the Men of Letters base and ultimately offers a deal in exchange for the name and location of every demon on Earth. At the same time, Abaddon has a ritual performed to have her vesselJosie Sands restored and begins a crusade to take over Hell and Earth. Her first attempt to kill the Winchesters fails thanks to the angel Gadreel. Abaddon has since been reshaping Hell in Crowley's absence, making it more chaotic and voiding all deals, taking the souls early. After Gadreel takes full possession of Sam, Dean makes a deal with Crowley to save him: in exchange for his freedom, Crowley helps Sam expel the angel. Crowley then starts a war against Abaddon for rule of Hell. To this end, he forms a reluctant alliance with Dean to find the First Blade, the only weapon that can kill a Knight of Hell. The two locate the retired demon Cain, the Father of Murder and founder and slaughterer of the Knights of Hell. Cain eventually agrees to help, giving Dean the Mark of Cain so that he can wield the Blade and the location of the First Blade which is at the bottom of the ocean. Even though Dean understands that Crowley was just using him to get the Blade, the two maintain their alliance as they need each other to defeat Abaddon who is the greater enemy. Eventually, working together, the Winchesters and Crowley find the First Blade, but Crowley takes it until they can locate Abaddon as he doesn't trust Sam and Dean not to try to kill him. Dean becomes obsessed with hunting and killing Abaddon and Sam joins him in this after learning that Abaddon is stealing souls to create an army of demons loyal only to her. Abaddon, using Crowley's son Gavin as leverage, forces Crowley to help her trap and kill the Winchesters. Crowley leads them to the First Blade, but subtly warns Dean that it is a trap when telling them where to meet him. In a final confrontation, the Mark of Cain grants Dean immunity to Abaddon's power and telekinesis, allowing him to gain the upper hand and finally kill her. Sam and Dean leave Crowley alive, but take the First Blade with them. Crowley however escapes with his son to spare him from returning to his time and dying.
In Do You Believe In Miracles?, Crowley reveals that Cain, the Father of Murder did not want to kill and commited suicide but the Mark of Cain proved too strong, forcing his return as a demon. The same thing happens to Dean who transforms into a demon.
Characteristics
“
They don't want anything, just death and destruction for its own sake.
”
— Dean, describing demons
A painting of demons.
Demons are the result of humansouls going to Hell and being tortured until no humanity is left in them, thus turning into demons - dark, malicious spirits that revel in pain, chaos, and death. According to Ruby, most demons forget what it means to be human. Some have even forgotten that they were once human. In general, demons engage in torture and destruction because it is fun or to avoid being tortured themselves. Some demons, however, are true believers in Lucifer's agenda to "cleanse" Earth, and actually consider themselves morally superior to humans.
There are many ways of becoming a demon, from making a deal with a Crossroad Demon, to being a witch, and making a deal with another demon. They manifest on Earth in the form of a long, slender cloud of black smoke. Crowley appears as the only exception, appearing as a blood-red cloud. Their true forms have not been shown onscreen, however Dean has seen their true forms, before he was taken to Hell. He says they look horrible even going as far to call Ruby "one ugly broad."
Once a soul becomes a demon, it gains the basic demonic powers (possession, superhuman strength, etc.) and from there, it can work its way up the ladder to positions of greater authority and power within Hell (possibly by torturing other souls). Often when a demon has used its powers, they leave a trace of sulfur in the nearby space, or if on a person, around the victim. This can give away the demon's presence, indicating to hunters that they are hunting a demon. Very powerful demons leave much more sulfur than average, as evidenced when Azazel kidnapped Sam. Some demons are sent back to Earth to accomplish certain tasks, such as causing disasters, spreading diseases, assassinating hunters, or manipulating people into committing crimes that will get them sent to Hell. To do this, they have to take a vessel or "meatsuit" in order to physically exist.
When they possess humans, they usually enter through their mouths. On one occasion, a demon entered a human via the eyes (as seen in the episode Phantom Traveler). Possessed humans often look exactly the same as they did before possession, the only noticeable change being that their eyes will sometimes change color (black, red, white, grey, or yellow depending on the demon possessing them). Demon possession also causes a chemical change in the circulatory system of the host; demon blood is known to be a unique serum and has certain attributes when ingested. Whenever they use their powers, they leave a trace of sulfur in the form of yellow dust. Angels and other supernatural beings can see the true faces of demons underneath their vessels.
Often under possession the human begins speaking and acting like the demon would. Upon exorcism the human - if they survived - retains no memory of their time during possession (unless they have been "awake" during possession, in which case the time of possession is a nightmare for them). The possessed humans also gain the powers of whichever demon is possessing them. Unlike angels, whose possession of a human vessel has to be with the vessel's consent, demons forcibly possess humans. People suffering from stress, fear or panic can be vulnerable to demonic possession. Demons abhor the name of God (which in Latin is Dio or Deus, but shown on the show as Christo).
Ruby being tortured by Alastair.
Demons apparently cannot leave a host body if they are gagged or their mouth is otherwise obstructed; Sam and Dean make use of this tactic against the Phantom Traveler via blindsiding it and taping its mouth shut, while both Meg and Ruby have been gagged while undergoing torture to prevent them from fleeing their hosts.
Demons have no quarrel with killing or torturing their own kind to achieve their goals. Tom, for example, tested the fake Colt by shooting his demonic "sister" Meg (Salvation). When pitted against other demons due to their individual goals, Ruby, Crowley, and Meg herself have killed their own kind without pause or remorse. High-ranking demons will casually sacrifice their underlings without hesitation. At the same time, though, some demons forge bonds with their siblings. Azazel, for example, referred to Meg and Tom as his "children" and was angered when Sam and Dean exorcised Meg and killed Tom (Devil's Trap).
A demon is "cured".
It is revealed that demons, although being tortured and twisted human souls, can be cured. Father Max Thompson, a member of Men of Letters, tried to find this cure, having made several experiments, but always ending with the demons' escape. Finally, he found that it is necessary to perform it on sacred ground and use purified blood to heal a demon. He injected his own purified blood into the demon hourly eight times and after the eighth he recited the exorcism achieving the cure. (Clip Show)
Powers and Abilities
After their spiritual decay is complete, demons develop supernatural abilities. It is unknown how demons' powers increase. However, it seems they do not gain it purely from age as Crowley is far more powerful than Meg and Ruby despite being hundreds of years younger than them.
Low-Level Powers
These abilities are possessed by all demons.
Demonic Possession - Like angels (besides Cupid, or so it seems) , most demons (only known exceptions are Acheri, Daeva and Hellhounds) require a human vessel or "meatsuit" to travel on Earth. Unlike angels, they do not need a person's consent. Also unlike angels, demons can possess corpses. It is easier to take control of people who are in states of heightened emotions or fear. They can also access their host's memories while possessing them (even if it is a brief possession). This ability can be thwarted by Anti-possession tattoos. Also under certain circumstances, the person being possessed can regain control if his or her will is strong enough. They can also possess humans who are already possessed by an angel (and probably by another demon), but the only problem is the angel can neutralize it, because angels are naturally stronger than demons. In many cases, the demon will ride the host hard for fun and once they vacate, the host will die.
Electromagnetic Interference - Demons, like spirits, often disrupt nearby electronics with their presence. Large numbers of demons can cause thunder storms.
Immortality - Demons have an indefinitely long lifespan and an arrested aging process.
Invulnerability - Injuries that would be fatal to humans, such as broken necks or gunshot wounds, have very little - if any - effect on demons. They can only be killed by special weapons or rituals. Unlike angels they don't always heal their vessels. If the "meatsuit" receives too much damage they simply find another human to possess, leaving their former vessel to die.
A demon throws Sam backwards with ease.
Super stamina - Demons never tire, and do not require food, water, oxygen, or sleep to sustain themselves. Sam states that they also do not get hot or cold and Dean states they do not need to urinate.
Super strength - Demons possess superior physical strength compared to that of humans; capable of physically overpowering humans. Demons can also overpower most monsters. Once, a demon (the Phantom Traveler demon) ripped open an airplane hatch with over 2 tons of pressure at over 1,000 feet above the ground. The higher ranking the demon, the stronger it is. The highest ranking demons can overpower low-level angels.
Supernatural Perception - Demons are able to see hidden supernatural activity and beings, such as Reapers, ghosts, and hellhounds.
Supernatural Senses - Demons have an enhanced sense of smell and taste, demonstrated as Crowley could identify Castiel was in Dean's Impala and that he and Raphael had been using dog's blood.
Telekinesis - Demons can move or suspend objects and other beings with their minds. Higher ranking demons can use this ability to pin their victims to walls or kill people by snapping their necks.
Soul Extraction - Demons have the ability to forcefully remove a person's soul from their body.
Mid-Level Powers
Used by some (mostly upper and some mid-tier), but not all, black-eyed demons, as well as higher-ranking demons.
Biokinesis - Some demons can manipulate the biology of other beings. Azazel, for example, was able to torture Dean by causing him to hemorrhage. Meg was also able to cause Crowley to cough up blood in a similar manner. Astaroth stopped Elizabeth's heart with a wave of her hand and Abaddon caused people to bleed from their eyes. Crowley was even able to cause a girl to explode by snapping his fingers.
Electrokinesis - Displayed by Azazel and Crowley. They could manipulate electronic equipment to their will. Also the demon possessing Isaac's corpse was able to switch on an old radio.
Invisibility - Some demons can become invisible to humans.
Brady kills Jessica with pyrokinesis.
Pyrokinesis - Some demons can generate and manipulate fire. Azazel, Abaddon and (probably) Brady have demonstrated this ability. Crowley can also manipulate fire; he extinguished a Holy Fire circle by snapping his fingers, and also pretended to set himself on fire.
Soul Reading - Some demons, particularly Crossroad Demons, can assess the condition of one's soul.
Spell Casting - Some demons can practice witchcraft, much like witches, like altering the range/space they occupy. Other demons are adept in Enochian magic which they use to protect themselves from Angels. Alastair knew of a spell that could allow him to banish an angel back to Heaven. Meg and Casey knew of spells that they could use while inside a Devil's Trap, allowing them to break free.
Teleportation - Some demons can travel from one place to another instantly, without occupying the space in between.
Terrakinesis - Limited; Some demons can create small earthquakes. This was once used to destroy a Devil's Trap drawn by Kevin Tran. (We Need To Talk About Kevin)
Thermokinesis - Certain demons such as Lilith and Crowley can emit great heat through their skin resulting in severe burns to whatever they touch. Crowley also once caused Ruby's knife to burn red hot by merely snapping his fingers, forcing Dean to drop it. (We Need To Talk About Kevin).
Healing - Used by Crowley, he is the only demon who has shown the ability to heal others out of the context of a deal, albeit a small wound. (All Dogs Go To Heaven)
Weather Manipulation - Some demons such as Meg and Father Gil are able to alter the weather to a limited extent such as creating sudden gusts of wind. More powerful demons like Azazel can create stronger winds and Abaddon could trigger thunder and lightning merely by screaming.
Regeneration - At least some demons can heal their hosts from any physical injury they sustain. Meg was able to heal several broken bones after falling from a window. Crowley, Meg and Ruby have all been shot on several occasions and show no signs of injury following the incident. Crowley has also healed his vessel after being severly burned by an angels white light and being stabbed through the shoulder by an angel blade. However, after leaving their host, any injuries the body has sustain reappear and the host dies. Oddly, while Crowley has vacated his vessel several times, many of his injuries (such as his burns) did not reappear on his host (though his host seems to have died so it is possible some of his injuries did reappear).
High-Level Powers
Knights of Hell, Multicolored, White-Eyed demons, Crowley and Azazel are the only ones to use these powers. They also possess all the previous abilities at enhanced levels and are incredibly strong. Lilith and Alastair are known to be powerful enough to fight and even overpower angels who rank low on the celestial chain of command. They will still flee when confronted by Archangels.
Lilith uses her White Light to obliterate the police station.
Access to/from Hell - High ranking demons such as Azazel, Alastair, and Crowley can easily teleport themselves back and forth between Earth and Hell, without the need for any complex summoning ritual or assistance. This however, varied among high-tier demons, as some were kept imprisoned due to unknown reasons and methods.
Dream Walking - Displayed by Azazel only on the special children. He could enter and control the dreams of his targets.
Mind Manipulation - Displayed by Crowley only, he was able to grant his illiterate son the ability to read simply by touching his head.
Enhanced Immunity - As a general rule, the more powerful the demon, the more resistant they are to harm and common anti-demon methods such as salt and holy water. High ranking demons like Alastair are immune to the Killing Touch of normal angels and both he and Abaddon are immune to the killing effects of the Demon-killing knife though it causes them pain. The Knights of Hell could only be killed by the First Blade and Cain, the original Knight, is completely immune to the knife to the point it doesn't even hurt him.
Memory Manipulation - Displayed by Abaddon, Crowley and Azazel. Abaddon was able to read the memories of individuals, Crowley stated that he "scrubbed" Kevin's short term memory and Azazel was able to erase Dean's memory of his conversation with Tessa. (In My Time of Dying)
Summoning - Displayed by Samhain. He could summon and control various monsters, ghosts and zombies.
Exorcism - Displayed by Abaddon and (possibly) Lilith. She forced a demon out of its host and back to Hell by choking its vessel. Lilith also claimed that she sent Ruby to Hell and then possessed her vessel.
White Light - Used by Lilith (Jus In Bello, No Rest for the Wicked) and Samhain (It's the Great Pumpkin, Sam Winchester). High ranking demons can use this to generate massive amounts of destructive energy that can obliterate large areas. This ability is extremely rare and are otherwise present only in the more powerful angelic beings.
Demonic Smiting - Cain, one of the first and most powerful demons, displayed the power to smite other demons similar to angels, but with a red glow rather than a white one.
Special Powers
These powers can generally only be accessed in the context of a Faustian Deal or performed in Hell.
Healing- In the context of a deal, crossroads demons can heal themselves and others of any wound as demonstrated by Azazel and Crowley. While in Hell, demons such as Alastair can heal any wound applied to their victim, so that they can continue to torture them again and again.
Reality Warping - Crossroads demons, and a few other Demons can grant humans a wish in exchange for their souls. It is worth noting that Azazel did not need to take souls, and could grant wishes from his own power, which he did in exchange for permission to enter the homes of special children, on their 6-month birthday. Lilith also claimed she could make deals without taking a soul but this was never confirmed.
Resurrection- One of the wishes demons can grant is the resurrection of a loved one. Crowley claims that, since he is now the king of Hell, he is strong enough to resurrect anybody in his care without a deal. He demonstrated this by resurrecting Samuel Campbell in Season 6; the 'patriarch' he 'took off the bench' in order to capture Alpha creatures, which Crowley hoped would lead him to the door of Purgatory. Azazel also displayed resurrecting, the young John Winchester after he killed him, in the context of a deal. He couldn't however resurrect Dean (possibly because he hadn't crossed over yet)- instead, he possessed a Reaper, who he used to do it for him.
Shapeshifting - Demons can take any form they wish while in Hell. Several demons were able to take the appearance of Sam and Dean while torturing Bobby Singer in Hell.
Devil's Trap - A Devil's Trap will hold a demon in place and prevent its escape. No matter how powerful the demon is, they are bound by the Trap. The Trap will also prevent low-level demons from using their powers, though Castiel's Enochian circle was able to completely bind even Alastair's abilities. It also locks a demon inside its host unless it is exorcised. For some reason, a demon inside a trap is usually unable to do anything to damage the integrity of the circle, which would allow its escape. A Devil's Trap engraved into a bullet and shot into Abaddon's head was shown to limit her movements like a normal Devil's Trap would and to bind her to the body she was possessing.
Salt - Demons are unable to cross a line of salt and can do very little to damage the line at all. They cannot open doors lined with salt if opening it would break the line. Salt can also be used to torture demons by making them ingest it or by injecting them with saltwater. It can also be put into shotgun rounds to hurt and knock back demons. However, Azazel is immune to this weakness and Crowley was hardly affected by rock salt shots, but he still found the experience painful.
Holy Water - Holy Water burns demons that come into contact with it, like acid. It has proved to be very effective against demons, as only Azazel and Lilith have been thought to be immune to it. However, certain high-tier demons seem to develop some resilience to it as Ruby practically laughed when Sam was about use it against Alastair because it would barely slow him down and it only affected Crowley and the Seven Deadly Sins for a very brief period of time.
Iron - A demon can't touch iron without its skin burning or cross it if it is used to erect a barrier, much like salt. Samhain and Alastair were immune to this weakness and Astaroth was resistant to it.
Palo Santo - Basically a wooden, hybridized version of salt and holy water. When a demon is stabbed with it, it causes the wound to smoke and painfully pins the demon to a single spot, immobilizing them long enough to perform an exorcism. Palo Santo isn't commonly used by many hunters due to the fact that it damages the hosts the demons are possessing. (The Magnificent Seven)
Flesh Sigil - By carving a particular sigil into a demon's possessed flesh, it is possible to lock the demon within its host and disable its powers, the most important one being teleportation. However, demons with these sigils are not bound to a single place and can roam around freely if not restrained by some other means. (The Devil You Know)
Holy Fire - Though not fatal to demons as it is to Angels, Holy Fire can cause demons extreme pain, as demonstrated when Castiel threw Meg into Holy Fire (Abandon All Hope...) and when Sam doused Abaddon in Holy Fire, causing her so much pain she fled both the scene and her vessel(Sacrifice).
Purified blood - The blood of a person who has confessed his/her sins is shown to be able to hurt demons if injected into them.
Banishing and Killing
Angels - Demons are inherently weaker than angels and therefore, are highly susceptible to the powers of angels. Even low-tier angels are able to easily overpower and kill almost all demons except the most powerful ones, demonstrating the apparent disparity in power between the two supernatural species. Only the highest ranking demons in the hierarchy of Hell could fight and overpower low-tier angels. However, even the most powerful demons are completely no match for Archangels, who can easily destroy them.
Death - Death can reap anything in existence, including demons, reapers, monsters, angels, and gods.
Exorcism - Will pull the demon out of its host and send it to Hell. Hosts may not survive. Before Sam and Dean learned that demons could be killed by the Colt or Ruby's Knife, exorcism was the only known method used by hunters, to stop demons. Reciting the exorcism backwards will force the demon back into its host. Very powerful demons are immune to exorcism (eg. Abaddon).
Eve - As Eve is the primordial monster and mother of all monsters, she is able to kill even the most powerful demon. She has demonstrated the ability to even block the powers of angels, further displaying her power.
God - Being omnipotent and omniscient, God can kill any demon He so desires.
Hellhounds - Although normally docile towards demons, hellhounds can overpower and kill demons just as easily as they can kill humans.
Leviathans - As monsters that predate the existence of angels, Leviathans have been shown to be capable of overpowering even Seraphim. As such, even the most powerful of demons are completely no match for Leviathans and can be easily killed by them. Furthermore, Leviathans view demonkind to be a "mutation" and in one instance, called demons to be "unimpressive", displaying a collective sense of hostility towards demons.
Physical Damage - Though demons themselves cannot be harmed by conventional means, severe damage sustained by their vessels (such as severed limbs) will greatly reduce their effectiveness in combat. Unlike angels, most demons are unable to heal their vessels. As such, if the vessel accumulates too much damage, the demon will be forced to vacate its host and search for a new vessel.
Ruby's Knife - The knife originally belonged to Ruby. It will kill a demon that is within a host if the wound dealt is a fatal one. Upper level demons are immune to the killing effects of the knife, the only definitive examples being Alastair, Abaddon and Cain. However most demons (with the exception of Cain) find contact with the knife extremely painful when not lethal.
The Colt - Much like Ruby's Knife, it will kill any demon that is shot while within a host if the shot is a fatal one. It is more powerful, however, as it affects upper level demons as well, even when the Knife does not.
Bones - If the bones belonging to the demon are burned, the demon will be killed much like a vengeful spirit. This can also be used to torture demons. This until recently was believed to be merely a rumor, however Bobby tested this method against a Crossroads Demon resulting in her death. Crowley may have been aware of this method as he tried to convince Bobby it was "a myth". This tactic is very difficult to use because it requires knowing the demon's human name from before it died and where they were buried, and many demons themselves can no longer remember they were ever human at all, let alone what their names were.
Death's Scythe - Death's Scythe can kill demons, as it is capable of reaping just about anything. Crowley confirms this when he gives Dean the scythe. (Two Minutes to Midnight)
Ingestion of Salt - Under some circumstances, the ingestion of large quantities of salt can force a demon to vacate its host. (I Believe The Children Are Our Future)
Unknown Virgin Sacrifice Spell - Ruby claimed to know a spell that would destroy any demon within a one mile radius. Not much is known about the ritual except that it requires cutting the heart out of a virgin. (Jus In Bello)
Upper Tier Demons - Crowley killed all but one demon from a demon hive in season five, so it can be assumed that a more powerful demon is able to destroy lower level demons. Many demons have also feared that their masters, such as Lilith or Azazel, will kill them if they betray them. However, this may have been through the use of a weapon as Crowley, Meg and Abaddon all later use an Angel Blade to kill demons. Cain however possessed the ability to smite lower demons in a similar manner to angels.
Demon Bomb - The Word of God tablet on demons describes a spell which can completely destroy demons. Kevin Tran is able to cast this spell and it is shown to work, disintegrating two demons and their vessels. (We Need To Talk About Kevin) Following instructions Kevin made in a notebook, Sam and Dean are later able to turn this into a bomb that Sam uses to kill three demons. (A Little Slice of Kevin) Sam and Dean later use it to kill four demons while rescuing Samandriel. (Torn and Frayed)
Demon Cure - It's possible to turn a demon into a human again if, in a sacred ground, a human injects his own "pure" blood in a Demon. The blood must be given hourly for eight hours. In the last dose, the blood must be fresh and the donor must tell before the exorcism: "Exorcizamus te, omnis immundus spiritus, hanc animam redintegra, lustra, lustra". (Clip Show)
Angel Blade - In Torn and Frayed, it is shown that an Angel Blade can be used to kill a demon. Sam uses one to kill two demons while rescuing Samandriel. It was earlier implied when Castiel drew his blade against Crowley. Crowley and Meg use Angel Blades to kill other demons when necessary.
Special Children - Sam Winchester developed special abilities almost especially tailored to hurt or kill demons. Due to training from Ruby and ingestion of demon blood, he first developed the power to pull demons out of humans. Later the powers advanced to killing demons outright, much like the knife or the Colt. Although unknown, it is assumed the other special children would have also been able to do this as well, had they survived, trained, and ingested demon blood.
Ghosts - Ghosts can pull Demons from their vessels as shown when John Winchester's spirit grabs Azazel.
Hallowed Ground - Low level demons, are unable to enter hallowed ground, however stronger ones can. It is unclear if this includes cemeteries as well as churches. (Salvation)
Hexbags - Hexbags can be used to hide people from demons as well as angels.
The most common and standard class of demons on the show, black-eyed demons possess only basic powers, such as super-strength and telekinesis. Effective defenses against these demons include Holy Water, salt, iron, a Devil's Trap, etc. Stronger black-eyed demons, such as Meg (Demon), are not barred in entering hallowed ground and one demon, Tammi, is shown to have the ability of causing internal bleeding and extensive magical knowledge, such as when she recites a ritual to exorcise Ruby from her body. Tammi was also able to stop a bullet shot from the Colt in mid-air. Although the Knights of Hell are black eyed demons, they are far more powerful and possess much greater abilities.
Crossroad demons have red eyes. Unlike normal demons that serve the King of Hell, Crossroad Demons tend to be more self-serving, often bargaining with desperate people, making deals in exchange for their souls after a certain amount of time (usually ten years). They can grant wishes, collect souls, teleport, and be summoned by digging a hole in the center of a crossroads and burying a box with a picture of the summoner, some graveyard dirt, and a bone from a black cat. Gifted with immense power, these demons usually possess attractive women to lure men into making deals, although there are exceptions.
White-eyed demons are considered the generals of demons. They're terrifyingly powerful and they rank the highest in the hierarchy of Hell, just under Lucifer himself. They inspired fear in their subordinates as all other demons seemed to be terrified of them. Being as powerful as they are, they were resistant to many demonic weaknesses. They were even capable of holding their own against regular angels. So far, the only known demons of this type are Lilith and Alastair, the former of which was the very first demon to be created.
Azazel is the only yellow-eyed demon to appear in any episode thus far. Besides having a unique durability threshold, advanced telekinesis, he could manipulate fire, control dreams, make electrical devices go haywire, and could even possess Reapers. The initial leader of the demon army, Azazel was the designer of the master plan to free Lucifer from Hell. He was impervious to Holy Water and most other conventional defenses against demons.
Knights of Hell are very powerful demons that were handpicked by Lucifer himself and created/trained by Cain, the Father of Murder. They are some of the first fallen demons. Legend among Men of Letters had it that archangels have destroyed all but at least one but in truth Cain himself killed them. They possess a number of abilities not seen from other types of demons. They are also nearly invulnerable, being immune to exorcism rites and even the demon-killing knife. The only weapon that can kill one is The First Blade. With Abaddon's death, Cain is the only Knight of Hell remaining.
Cambions
Cambions are a demon race that are half demon but are also half human, they are created when a demon reproduces with a human, via their vessel. Jesse Turner is the only known Cambion. Their power grows when Lucifer is out of his cage.
The Multicolor-Eyed Demon, Samhain, the origin of Halloween, who can be summoned through three blood sacrifices every 600 years.
The Seven Deadly Sins, the physical embodiments of the Seven Cardinal Vices.
The Daeva, Zoroastrian shadow demons, who are sometimes used by other demons to attack targets, but are difficult to control, and can turn on the demon controlling them. They do not seem to require a host.
The demons that cause disasters, a rare type, each causes a specific type of disasters, both natural or man made as on the episode Phantom Traveler (causing airplane crashes). They are also quite unique, as their form on Earth resembles insects more than smoke, they enter their victims through the eyes, and only the iris's turn black when possessing a victim.
The Acheri, demons from Indian mythology that can spread disease, appearing as young girls with felinistic features.
Hellhounds - Demonic canines that drag souls to Hell upon their deal expiring. They do not require a host.
Deva/Reshef - Demon of Plague and Pestilence, Croatoan Virus itself, seen in the eyeballs in "Croatoan". May be one of the Demons that causes disasters.
Jesse Turner, a boy born from a woman while possessed by a demon, was meant to become the Anti-Christ, destined to help Lucifer not only destroy humanity, but also destroy the Host of Heaven. Lucifer's presence on Earth increased his powers tremendously. Even though he was still a child, he was powerful enough to turn Castiel into a toy figure. However, thanks to Sam and Dean's encouragement, Jesse rejected his destiny and went into hiding.
The first demon ever to appear (the disaster demon in Phantom Traveler) was notably different from the other demons that would later appear. This was the result of several retcons by the writer as they developed the demon lore.
Demons' true forms are almost never seen on Supernatural, but if one looks carefully in All Hell Breaks Loose - Part 2 after John pulls Azazel out of his vessel, a decaying skull-like face is visible within Azazel's smoke form. This is arguably also seen in demons stabbed with the demon knife or an angel blade, when their vessels flash orange and the skeleton beneath is visible.
Demons are the main antagonists of the Show, and the most recurring one. Upto date three main villains have been demons, specifically Azazel, Lilith and Crowley. Likewise three secondary villains have also been demons, specifically Meg, Alastair and Ruby.
In Frontierland, Samuel Colt kills two demons who, upon death, flash blue opposed to the regular red-orange. It is never explained how the demons differed from others.
