Elves are magical creatures known to associate with Santa Claus.
In a previous timeline, during Quentin Coldwater's first year at Brakebills University, he asked if Neeny Bigby was an elf due to seeing the professor's wings, but Neeny Bigby told him he was a Pixie.
When Santa Claus needed help getting a book from the Poison Room to finish a spell, he sent a number of elves to infiltrate the Library of the Neitherlands. After returning, however, the elves later died and Nick was charged with possession of restricted materials and murder on Library property before being imprisoned by the Order.
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