A ghost is the soul, or spirit, of a deceased person that can appear in a visible manifestation to the living. Unlike popular culture, ghosts do not appear as transparent beings, but instead as normal humans, oftentimes adorned in the same outfits they've died in. Some of them seem unable to realize that they are dead, while others use this to their advantage, tormenting the lives of their fellow spirits or mortal victims.  According to psychic medium Billie Dean Howard , a great evil can attract ghosts, as spirits with particularly negative emotions can dramatically affect reality. Ghosts are perceptible to her the same way as winter humidity; the ghosts of evil people or killers can cause disorientation and oppression in a medium, especially when more than one is in a room; Howard compares this to "termites in the walls". So far, ghosts have appeared in all seasons except for Asylum.
Characteristics and Powers
How strictly these "rules" are applied varies and has never been clearly defined in the series itself. Edward Mordrake is one such example of an exception to these rules.
- Trapped in the Place of Their Death: Ghosts are tethered to the area of their death and can not normally leave it. This restriction does not apply on Halloween, Devil's Night, or if they are released by magical means. Generally, ghosts tend to exist in places where many horrible, disturbing events have taken place. Billie Dean Howard describes these locations like a "battery" for evil energy, absorbing the negative feelings, emotions, and events of the heinous crimes that have occurred in their depths. As a result, these locations become a trap for individuals that die on their premises, ensnaring their spirits to the mortal world due to unfinished business they have in life. To avoid becoming trapped in one such location, one must not only leave the inside of a cursed building before dying, but also the building's outside perimeter, such as a garden or sidewalk, as these places are still affected by the restriction. In the case of mass murder in outdoor areas, the ghosts infest the entire outside, as is the case for the lost colony of Roanoke that haunts the woods of North Carolina.
- Exist Indefinitely: By their very definition, ghosts will exist forever and never die, as they are the spirits of those who are already deceased. Some ghosts remain trapped in an unbreakable chain for all of eternity, repeating themselves over and over again on an endless loop until they find their purpose. This does not mean, however, that upon finding their purpose they will be able to leave the place of their death. On the contrary, after becoming aware of their new status, they are able to act on the physical plane, regaining memorization and cognitive abilities rather than being disoriented shells of the people they once were .
- Ageless: Ghosts appear at the same age they were when they died and in the same clothes they were wearing upon the moment of their death, but they can change this in their ghostly state.
- Shapeshifting: Some ghosts possess the ability to change their physical appearance, as in the case of Moira O'Hara. Moira's ghost appears as a seductive young woman to men, while women and those able to see beyond physical beauty see her as an elderly woman.
- Intangibility: Ghosts can become tangible or intangible at will. Although they have no physical mass, ghosts can consciously choose to manifest in a corporeal form to interact with the living, as well as an incorporeal form, during which no human can perceive or touch them.
- Invisibility: Ghosts can become seen or unseen at will. Despite this, psychic mediums - such as Billie Dean Howard or Cricket Marlowe - can see and communicate with them indefinitely. Ghosts that have made it to the afterlife are able to communicate to the living via a medium's assistance. Witches can communicate with ghosts using a spirit board, although this can be risky, as this method may inadvertently release nasty spirits other than the one spirit they are attempting to contact.
- Transmutation: Ghosts do not follow the rules and laws of physics, and are able to move instantaneously from one location to another (within the confines of the place of their death) without physically occupying the space in between.
- Telekinesis: Some ghosts, such as the Butcher, can move objects with their mind, as displayed when she shattered several glass windows without physically touching them. This may be due to having sold her soul to the witch Scáthach, however, therefore binding her to the curse of the October Blood Moon which has granted her this ability, allowing her to more easily carry out whatever tasks the witch desires of her.
- Demonic Manipulation (Possibly): Some ghosts may or may not have some relation to demons; a mystery which might have been demonstrated through the very limited control Sally and James March have attempted to exert over the Addiction Demon. Upon finding Gabriel being violently raped by the Demon, Sally tells him that it will go away if he says "I love you Sally". After ushering these words, the Demon vanishes. Sometime later, James March threatens Sally that he will set the Demon on her for disobeying him, causing her to remember a traumatic incident where she was periodically tortured by it for three days. As to whether or not the Demon follows their commands, or is capable of its own independent thoughts and actions, has yet to be determined. James has stated that he must "protect" Sally from the Demon's malevolence, and elaborates that it has apparently been lurking in the hotel for some time by feeding on the suffering and fear of drug addicts, where it has since remained a dangerous enemy to him.
- Witchcraft on Ghosts: The effects that witchcraft has on ghosts is not entirely clear. Some magical powers, such as Injury transference, has no effect on them, as ghosts do not feel pain as physical living beings do, nor do they possess tangible bodies  . A ritualistic spell performed by Zoe, Queenie, and Nan was shown to be able to turn ghosts back into living, breathing human beings, as in the case of the Axeman. Telekinesis may affect ghosts, although it was only displayed on the Axeman after he was resurrected and alive once more, leaving its full effectiveness against ghosts unknown.
- The Blood Moon Curse: Some ghosts, such as the Roanoke Colony, are prevented from murdering humans, as they can only do so during a phase of the moon in October known as the Blood Moon, when the full moon appears red in color. This differs from other seasons, in which there is no rule denying ghosts from killing (eg. James Patrick March, Tate Langdon).
This may be explained in the fact that the Roanoke ghosts are bound by a curse bestowed upon them by the witch Scáthach, thereby forcing them to abide by the will of her magic. As a result, the Roanoke ghosts also appear to look much less human in appearance than ghosts shown in previous seasons, displaying characteristics more akin to diseased or rotting living corpses.
A ghost will only be allowed to pass on to the next life if they have overcome the issues that are keeping them on Earth. Although the details of the afterlife are unclear, it is described by Billie Dean Howard as blissful, beautiful, and safe; Papa Legba states to Nan upon her death that the afterlife is full of treats for girls just like her. It seems that all wishes and desires most sought by the deceased become true; Addy is a beautiful girl on the other side, Elsa Mars becomes a famous singer and is reunited with her troupe of freaks, and Donovan is in a happy place where it is always a Saturday morning and the air smells of pancakes with blueberries.
- ↑ Episode: Spooky Little Girl
- ↑ Episode: Birth
- ↑ 3.0 3.1 Episode: Be Our Guest
- ↑ Episode: Halloween: Part 1
- ↑ Episode: Devil's Night
- ↑ 6.0 6.1 Episode: The Axeman Cometh
- ↑ Episode: Halloween: Part 2
- ↑ 8.0 8.1 Episode: Battle Royale
- ↑ Episode: Chapter 1
- ↑ Episode: Room 33