What are Avatars and Entities Anyway?
Since there's been some questioning from the non-TMA side of fandoms, here are the basic definitions of Avatars, Fear Entities, and each specific one.
There are 15 Fear Entities in The Magnus Archive (Podcast). They are supernatural beings that feed on fear of specific kind. The division is a little arbitrary and there are overlaps between them, but this is the system used in the universe, so we are going with it!
Each has Avatars, manifestations and artefacts that cause that fear in living beings (yes, not only humans, if very heavily humans). Artefacts are just that, objects that cause creepy and supernatural things to happen. Manifestations are living counterparts to artefacts that were never anything but. We are not concerned with them.
Avatars are people who used to be human, but through choice of circumstance came to represent, serve, and/or cause specific type of fear. The choice needs to be there, but not necessarily be informed or enthusiastic.
Each of the Fears has obvious interpretations associated with them, but often cover metaphorical fears too. And, some fears can be a part of multiple. (eg. the fear of insignificance can be an element of The Vast, or the Lonely)
The Buried. The fear of small, enclosed spaces, of suffocation, and being trapped. Often associated with drowning, being buried alive, being overwhelmed.
The Corruption. The fear of corruption, disease, and disgust. Often associated with insects, decay, illness, and unhealthy love.
The Dark. The fear of being unable to see, of unseen, of the dark itself. Often associated with literal dark spaces, blindness, hiding monsters, and unknown.
The Desolation. The fear of pain and loss, destruction, and senseless devastation. Often associated with fire, war*, and destroyed potential.
The End. The fear of death - most straightforward of them all. Often associated with remains and undead creatures.
The Extinction. The fear of a large scale catastrophe, death, replacement. Often associated with alarmist rhetoric and of destruction of humankind by our own hands. But, it does not has to be a complete destruction of an entire species. (eg. A disappearing culture can fall under extinction too. Or an apocalyptic, but not barren future.)
The Eye. A fear of being watched, known, and exposed. Often associated with curiosity, stalking, and surveillance.
The Flesh. The fear of being seen as meat, of realisation that you are meat, of your flesh being wrong. Often associated with animals, with the meat-packing industry, and with body dysmorphia and dysphoria.
The Hunt. The fear of being chased and hunted. Often associated with instincts, animals, and monsters.
The Lonely. The fear of isolation, abandonment, and disconnection. Often associated with fog, empty spaces, (faceless) crowds*, and suburbs.
The Slaughter. The fear of senseless violence and pain; unlike the Desolation is concerned directly with the living, not objects or possibility. Often associated with murder, and war*.
The Spiral. The fear of one's own mind, of madness, and of deception. Often associated with fractals, illusions, and neurodiversity of all kinds.
The Stranger. The fear of unfamiliar and uncanny. Often associated with uncanny valley (dolls, mannequins, taxidermy), circuses and performances, and faceless crowds*.
The Vast. The fear of space and insignificance. Often associated with heights, large open spaces (ocean, sky, space), and losing oneself*.
The Web. The fear of being manipulated, controlled, and trapped*, of having no free will. Often associated with spiders and puppets*.
*might be a part of multiple Fears depending on circumstances