Elves are creatures of light that appear in Norse mythology.They come from Alfheim which is one of The Nine Worlds that are held in the branches and roots of the world tree Yggdrasil. Their lord is Frey father of Magnus Chase. This world or realm is mentioned in The Sword of Summer.
Elves are one of the three mortal races. They look like humans, but they need the constant sunlight, like on Alfheim. Without it, they need sleep and will eventually fade away and die. They look much like humans but have a few nonhuman traits. These traits include pointy ears, green veins, and reflective eyes. They also smell like pine needles and woodsmoke.
They have become much like humans, losing connection to the other realms and magic. Elves were once skilled magicians and archers. Nowadays many elves spend their time looking at pixel screens and they believe humans and Midgard are myths, wearing tights and living in castles. Elves do not have much tolerance for things that aren't perfect, including their own children (as evident in Hearthstone's case).
- Svartalfar, or Black Elves, are not Elves but a subset of Dwarves.