Species List

Vampires (also known as Vampyrs and as Van-Tal in the dimension Pylea) were a species of soulless, undead demons that could only exist on Earth by leaving their own dimension and possessing human corpses. They were hybrids, and were thus despised by other, "purer" demon species. They were well-known for feeding on the blood of mammals, particularly humans.

Demons are malevolent spirits that are the direct opposites to Angels. They are created from human souls that have endured extensive torture in Hell by Alastair and other demons. In this process, they become corrupted, extremely evil, and also very powerful. Similar to Angels, they require a Vessel to walk the Earth, though are able to roam in their smoke form.

A hunter is a being, usually a human, who hunts down the supernatural and saves people from monsters, demons, ghosts and other creatures.

Werewolves:
Werewolves, also known as Lycanthropes, are a race of partially-human supernatural creatures, able to morph into a combination of human and wolf, that have been encountered by hunters such as Sam and Dean Winchester. It has been stated that werewolves and skinwalkers are cousins. In the early stages it can sometimes be cured with a transfusion of live blood from the sire werewolf.

Hybrids:
Hybrids possess both the strengths and some of the weaknesses of their parent races, along with powerful attributes unique to themselves alone due to their combined heritage. For werewolf-vampire hybrids, this includes Day Walking and being able to transform into a wolf without the Full Moon's influence. For siphoner-vampire hybrids, they retain their ability to siphon magic and their own vampirism as a power source for their use in witchcraft; as they did not possess their own magic as humans, this is a skill that makes them powerful.

Witches are supernatural beings who are born with the power to affect change by magical means (Witchcraft). While many witches are the self-proclaimed "Keepers of the Balance," other witches have been known to work against the Balance and use their power for personal gain.

Angels are powerful celestial beings of light created by God to serve as his attendants and messengers, but also as his soldiers and warriors in his war against Lucifer and his demons. They are native to Heaven and are imbued with considerable power.
Angels are one of the most powerful entities in the series, generally outclassing all demons, monsters, ghosts, and other supernatural creatures with the exception of the Leviathans, The Antichrist, Eve, The Horsemen, The Darkness, and God himself.

Dragons are a very rare race of supernatural creatures that have not been hunted or even seen for over 700 years. In fact, they are so rare that most veteran hunters (like Bobby Singer) dismiss their existence as purely fictional. Only a select few know otherwise, and even they believe dragons were extinct. They are similar to the traditional dragons in lore, but, whilst in confined spaces, they appear more like humanoid creatures rather than the winged beasts shown in traditional art. There are descriptions of them appearing as giant bat-like creatures when in their true forms.
The dragons' motives were to open Purgatory to free Eve, Mother of All. To do this they abducted young female virgins so they could sacrifice one of them to become the vessel for Eve.

Succubi, and their male counterparts Incubi, are a breed of supernatural beings that feed off the life force and sexual energy of living beings. In folklore, Succubi and Incubi were once believed to be demons that preyed on men and women in their sleep for sexual intercourse. Although supernatural, Succubi and Incubi are not demonic in nature.

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 Crossroads 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.

Reapers are angels that serve Death. They assist in maintaining the Natural Order and used to be thought as completely neutral, aligned with neither Heaven nor Hell nor Purgatory. According to Castiel, Reapers will sometimes appear in mass gatherings in prelude to a great disaster such as the eruption of Mount Vesuvius in Pompeii.
Being the servants of Death, Reapers are one of the most recurring supernatural creatures in the series.

Sirens are a type of supernatural creature that have been encountered by Sam and Dean Winchester that can take different forms to lure and compel humans to perform drastic acts to prove their love and devotion. These acts are usually destructive or violent and usually result in deaths of one kind or another. Not much is known about them, however, due to the fact that they are creatures rarely seen outside of Greece.

The Leviathans (also called The Old Ones, Chompers, or Levis for short) are primordial monsters that served as God's very first beasts. Thus, they predate angels, humans, and the soul itself. The creatures proved to be too hungry and destructive, so God created Purgatory and locked them inside. They were inadvertently released when Castiel opened Purgatory and absorbed all the souls inside in order to defeat Raphael.
Upon their release, the Leviathans attempted to conquer the North America and place themselves as the new dominant species on the planet, subsequently harvesting the human race as their primary and abundant food source while eliminating all other competitors and threats to their food.
This attempt to subjugate mankind was thwarted through the combined efforts of hunters, angels, demons and even monsters but was ultimately stopped by Dean Winchester and Castiel after they managed to defeat the Leviathans leader and architect of their plan: Dick Roman. According to Crowley the Leviathans themselves disbanded after Dick's death and are scattered but their actual fate is unclear.