Daedra are divine beings that did not take part in the creation of Mundus, and thus retain the full breadth of their power. They have a very real impact on the mortal realm; in one way or another, Daedric influence touches everyone on Tamriel.
The word "Daedra" is of Aldmeri origin, and roughly means "not our ancestors", as opposed to Aedra—"ancestors".
Daedra are often referred to as demons, but this is misleading. All Daedra have a penchant for extremes and are therefore capable of tremendous acts of devastation, but their different spheres make them apply their power in different ways, and their infinite diversity makes speaking about them generally difficult. Thus, it is often impossible to accurately label them as "good" or "evil"; the one thing that can be stated with certainty is the Daedra are beyond mortal comprehension.
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Artwork credit: Erika-Xero
Daedra come in many forms. Undoubtedly there are true Daedra, such as the Daedra Princes and highly intelligent Dremora. There are many lesser beings known to be in league with these greater powers, but whether each type constitutes actual Daedra is unknown.
A Daedroth's physical form can be ruined, but it cannot be truly killed; the soul (more specifically known as the animus or vestige) of a slain Daedroth returns to the void of Oblivion until it manages to coalesce into a physical form again.
Daedra are great imitators, and their creations are described as mimicking things found on Nirn in an outlandish or even corrupted way.
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Daedric Princes (sometimes referred to as Daedra Lords) are the most powerful of the Daedra, and thus most commonly worshipped as gods. Each has a particular sphere, which it is said to govern. The various Daedric Princes and their spheres are listed below. Daedric Princes may assume a typically masculine or a typically feminine form, sometimes both. They are usually referred to as Princes regardless of what gender they appear most frequently as.
Azura, the Queen of Dawn and Dusk, also known as Azura of the Crimson Gate, the Mother Soul, Moonshadow, Mother of the Rose, Queen of the Night Sky, and the Rim of all Holes, and called Azurah by the Khajiit, is a Daedric Prince whose sphere is dawn and dusk—the magic in-between realms of twilight—as well as mystery and magic, fate and prophecy, and vanity and egotism. Azura is one of the few Daedra who maintains the appearance of being "good" by mortal standards, and reportedly feels more concern for the well-being of her mortal subjects than other Daedric Princes. It is said she wants their love above all else, and for her worshippers to love themselves.
Art Credit: Ray Lederer
Boethiah , known as the Prince of Plots, the Dark Warrior, Deceiver of Nations, Queen of Shadows, Goddess of Destruction, Hunger, and Fount of Inspiration, is a Daedric Prince who rules over deceit, conspiracy, secret plots of murder, assassination, treason, and unlawful overthrow of authority. This sphere is destructive in nature, and Boethiah's destructiveness comes from inspiring the arms of mortal warriors. The Dark Warrior has been described as "cold" and "impersonal", "cruel", and one of the more "demonic" of the Daedra lords. Worshippers are known to hold bloody competitions in Boethiah's honor, battling—even killing—each other, for Boethiah is said to care only for their blood.
Clavicus Vile, also known as the Prince of Trickery and Bargains, the Master of Insidious Wishes, and Nycot to some Second Era cultists who lacked the ability to read Daedric script, is a Daedric Prince whose sphere is the granting of power and wishes through ritual invocations and pacts. He is seen as one of the more "sophisticated" of the Daedric Princes, and often appears in the guise of a jovial Skaafin, a race of horned Daedra that inhabit the Fields of Regret, his realm in Oblivion.
Clavicus finds eternity to be "boring", so he finds entertainment in watching mortals and occasionally meddling in their affairs.
Art Credit: Ray Lederer
Hermaeus Mora, the Demon of Knowledge, the Master of the Tides of Fate, Gardener of Men, Prince of Fate, Lord of Secrets, the Golden Eye, Ur-Daedra, the Abyssal Cephaliarch, Old Antecedent, Scryer, Inevitable Knower—