Hellhounds

"Hellhounds. Demonic pit bulls."

- Sam, talking about Hellhounds

Hellhounds are ballistic and maniacal canine-like beasts of the supernatural world, specifically Hell (hence the name), which are known to serve demons. Described as demonic pitbulls, hellhounds are ferocious, terrifying entities that inspire fear in humans, demons and even angels.

With time they became tasked with collecting the souls of humans whose deals are come due. In such circumstances, hellhounds can only be seen by those whom they have come for, making them a sort of reaper of the damned. In later seasons, hellhounds are seen working for various other demons (not just Crossroad Demons), usually acting as foot soldiers, guard dogs and/or assassins.

According to Crowley, no demon knows the hounds better than him. As the "Demonic pit bulls" of Hell, Hellhounds are also one of the most recurring supernatural creatures in the series.

History
According to Crowley, after God started creating the Universe, he made an abundance of creatures, including the Hellhounds, which he intended to be used as "the Creator's best friends". However, the Hellhounds proved to be too vicious, so God decided to destroy them all. But Lucifer, once he fell from Heaven, managed to rescue one of the Hellhounds, Ramsey, who was pregnant, and from Ramsey the hellhound population regrew.

And from that moment on over the millennia, Hellhounds served as "demonic pit bulls" to demons, going after humans who had sold their souls.

Characteristics
Hellhounds are voracious, tenacious, and intelligent. Once a hound has the scent of its target, it has it for life and will never give up the hunt until one or the other is dead, or unless its master calls it off. They can be clever, almost impossible to trick or distract, and are not disinclined to improvisation in order to get to their prey. Hellhounds will often physically rip their victims to shreds in order to collect their souls. In some cases, however, their mere presence is enough to literally scare people to death. Other times, the victims will be driven to commit suicide.

They appear as ferocious black dogs with red eyes. They vary in size, ranging from standard large-sized dogs, to that of a small horse. They generate some kind of black aura around themselves, making them appear made of shadows.

As dogs, they are loyal, and answer only to the demons they serve; they cannot be swayed or bargained with, either. Not even Crowley could devise a way to throw them off, short of using a bigger hound of his own to kill them.

Exactly how they are controlled is unclear. They have been shown to understand verbal commands, but sometimes they have stopped simply because the demon they serve changed their mind.

Hellhounds are vulnerable to iron, salt, The Colt, Angel Blades and Ruby's knife. They are generally invisible unless the human they are after made a crossroads deal or is looking at them with an object scorched with Holy Fire, such as Hellhound Glasses.

Masters
Any demon can command a hellhound, but very few of them can overpower one, or at least many at the same time. It is unknown if any demon or even angels could overpower one without the use of certain weapons. However, an archangel could easily destroy one. In the episode The Devil You Know, it is revealed that Crowley keeps a hellhound as a pet. This hellhound is bigger than most other hellhounds and Crowley uses it to fight off another, smaller hellhound.

However, only Lucifer could command their mother, Ramsey.

Powers and Abilities

 * Invisibility - Hellhounds are invisible to humans, except under special circumstances. However, supernatural creatures, such as demons and angels, can see them. They can also be seen by the humans they are assigned to hunt and through an object scorched with Holy Fire.
 * Invulnerability - Hellhounds cannot be killed by conventional means or weapons. However, weapons like Ruby's Knife, or an Angel blade, can kill them.
 * Super Senses - Hellhounds' sense are extremely heightened.
 * Super Speed - Hellhounds are much faster than humans.
 * Super Stamina - Once a hellhound has the scent of its prey, it will never stop hunting him or her, unless it is killed or called off by its master.
 * Super Strength - Hellhounds are very strong, they are able to kill humans and demons.
 * Tracking - They can locate any human or demon they are sent after.
 * Hallucinations -  When close to their prey, hellhounds cause their victims to experience hallucinations, so as to frighten them out of hiding and leave them defenseless.

Harming

 * Salt - It serves as a barrier which they cannot pass. Salt also harms hellhounds.
 * Goofer Dust - It can be used to create a barrier, like salt.
 * Devil's Shoestring - This herb can serve as a barrier preventing Hellhounds from passing through a door it's placed over.

Killing

 * Demon-Killing Knife - Ruby's knife could kill a hellhound.
 * The Colt - This gun was effective on hellhounds.
 * Angel Blades - Hellhounds could be killed by angel blades.
 * God - God was the one who wiped out the entire species of hellhounds except Ramsey.
 * Iron - Hellhounds were killed by a homemade bomb containing iron nails.

Known hellhounds

 * Arthur's hellhound
 * Crowley's Hellhound Pack
 * Crowley's unnamed hellhound
 * Juliet
 * Meg's Hellhound Pack
 * Ramsey

Appearances
Although only appearing only once or twice every few seasons but as the "demonic pit bulls" of hell, Hellhounds are one of the most recurring supernatural entities in the series besides demons, appearing in a total of 12 episodes.
 * Season 2
 * Crossroad Blues
 * Season 3
 * Time Is on My Side
 * No Rest for the Wicked
 * Season 4
 * Lazarus Rising
 * Yellow Fever
 * Season 5
 * Abandon All Hope...
 * The Devil You Know
 * Season 6
 * Weekend At Bobby's
 * Caged Heat
 * Season 8
 * Trial and Error
 * Season 9
 * King of the Damned
 * Season 11
 * Beyond the Mat
 * Season 12
 * Somewhere Between Heaven and Hell
 * There's Something About Mary
 * ​Season 13
 * The Scorpion and The Frog