- Demons were originally human, but during their time in hell they lose all trace of their humanity.
- Appear as a ‘black smoke’ in incorporeal form
- Presence may leave traces of sulfur
- Manifest by possessing humans
- Can resurrect people but only if a deal is made
- A possessed human will be unaffected by physical harm, until dispossessed
- Exorcism will drive the demon from its human host and send it to hell
- Have a range of abilities including mind control, telepathy, telekinesis and super strength
- Up until Season 3 the only method of permanent dispatch was to shoot them with the Colt. In episode 3.01 The Magnificent Seven the character Ruby introduced a Knife that could kill demons as well. In episode 3.04 Sin City Bobby rebuilds the Colt with Ruby's help.
- Humans possessed by demons exhibit black, red, yellow or white eyes depending on the demon involved.
- At the end of 2.14 Born Under a Bad Sign after San is possessed, Bobby gives the boys charms to protect against possession. In 3.12 Jus in Bello, we find out the boys have had the protection symbol tattooed on their chest, somewhat over their hearts.
- In 3.12 Jus in Bello, Ruby gives the boys a Hex Bag to help disguise their whereabouts from Lilith
- Other demons, or people close to the gates of Hell (like Dean in episode 3.16 No Rest For The Wicked) see the "real" face of demons, not just the body they chose to walk earth.
Lucifer is first mentioned in 3.04 Sin City by the demon possessing Casey, who claims that demons have a belief system just like humans, but while humans believe in God as a higher power, demons believe in Lucifer, the fallen angel. Casey reminds Dean that Lucifer was once an angel, and that his name also means "Lightbearer (Lightbringer)", as he was the one to stand up against God, igniting a rebellion in heaven.
Casey says that no one has ever actually seen Lucifer.
- Has white eyes (iris and pupil)
- Appears in the form of a female child
- Has the power to cause explosions
- Presence in an area will be presaged by cattle deaths, electrical storms and temperature fluctuations.
- Makes clocks stop, and electrical devices go haywire
- Is impervious to Holy Water
- Has yellow eyes (iris and pupil)
- Impervious to the salt barrier
- Vulnerable to the Colt
- Can also possess other supernatural beings such as a Reaper
- Casey in 3.04 Sin City claimed he was Azazel
- Meg Masters refers to the Yellow-Eyed Demon as "Father" 1.11 Scarecrow
- In 1.22 Devil's Trap, the Yellow-Eyed Demon refers to Meg as his daughter, and Tom as his son.
The Crossroad Demon makes bargains with people, granting a wish in exchange for claiming their life and soul.
- Has red eyes (all except for a black pupil)
- Makes deals with
- Robert Johnson in 2.08 Crossroad Blues in 1930
- George Darrow, Sean Boyden, Silvia Growman and Evan Hudson in 1996 in 2.08 Crossroad Blues
- Dean in 2.08 Crossroad Blues
- Dean in 2.22 All Hell Breaks Loose: Part Two
- In 3.05 Bedtime Stories she reveals that 'someone higher' than her holds the contract and describes herself as 'a saleswoman'
- Is killed by Sam with the Colt in 3.05 Bedtime Stories.
- Not an homogeneous group, they display a range of abilities and powers
- Eyes turn entirely black during possession, though this can seemingly be turned on and off.
- They are impervious to hallowed ground ("that may work in the minor league, but not with me" - Meg, Salvation), but not to Holy Water
- They can be exorcised and thus the demon returned to Hell
- Restricted by the salt barrier
- Vulnerable to the Colt.
- Vulnerable to the blade owned by Ruby
- Can resist exorcism (Meg!Demon in 2.14 Born Under a Bad Sign)
- Can trap themselves within their human host using a binding spell
- Can communicate
- via the Goblet of blood with Yellow-Eyed Demon
- via EVP 1.04 Phantom Traveler
- Tammi - the black-eyed demon in 3.09 Malleus Maleficarum - appears to be more powerful than other black-eyed demons. Similar to Azazel, she can pin both Sam and Dean to the wall, and use her power to kill at a distance. She causes internal bleeding in Dean, similar to that caused by Azazel, seen in 1.22 Devil's Trap. Tammi stops a bullet in from The Colt in mid-air when Sam tries to shoot her.
Examples of Black-eyed demons
- Airplane Demon from 1.04 Phantom Traveler
- Meg!Demon (possesses Meg Masters and Sam)
- Duane Tanner
- Seven Deadly Sins
- Father Gil
- Acheri Demon: Summoned by Ava in against the other Special Children. Sam says they are demons that manifest as children. He dispels it using an iron rod. It cannot cross a salt barrier.2.21 All Hell Breaks Loose: Part One
- Seven Deadly Sins