The word "Eldritch" as in "Eldritch Horror" comes from the same root as the word Elf.
Elves were terrifying forest creatures akin to djinn. They were horrors that would give you amazing things at a terrible cost, and from the medieval period we hear only the stories of the rare survivors of their actions.
(like Tam Lin who was given temporary immortality at the cost of being the slave of the elf queen and being tithed to hell unless some other mortal saved him)
or would literally kill you and drag your soul to hell if they encountered you
(the Wild Hunt)
or tricksters who would ask you for a favor and in the process attempt to steal you away as a slave
(there was a midwife who was summoned to help with an elven childbirth, after she was done the husband tried to get her to eat or drink of their food, but the elf-wife had warned her that if she did she would become his property)
They were not cutesy Santa's helpers or Legolases (Legolai?) or whatever flavor anime blonde girl you're thinking of. They were horrors you hoped to never encounter, the dark things in the forest looking for their next plaything.
Ah, I was referring to physicality not the personality. They hold the Trickster archetype prior to Sinter Klaus and Tolkien for sure. At least in Asian cultures a fox (trickster) sometimes has wisdom.
Have you read Susanna Clarke? Her faeries are like djinn if djinn had hopes and plans of their own. Amoral, egotistical, slightly insane, and sometimes petty beings of immense power, born of ancient pacts with the elements of nature.
> Elves were more imps than tall, eternal sages. See Santa’s elves.
Post-christian elves were diminutive. But Tolkien was using pre-christian myths as a foundation for the LOTR. The elves leaving Middle Earth is a metaphor for the old legends being replaced by sanitised children’s stories.
