The earliest literary treatment of Loki myths is from the 9th century. His depiction is complicated and contradictory. Many people advanced theories, including linguist and folklorist Jacob Grimm, who thought Loki the god of fire, like Prometheus (who brought fire to man and for his disobedience to Zeus was chained to a rock where his liver was eaten and regenerated each day) or Lucifer (whose name means 'light-bearer'); Jan de Vries, who considered Loki a typical trickster god; and Georges Dumezil, who considered Loki an incarnation of "impulsive intelligence."
In the Edda Loki transforms himself into a mare to lure away a stallion and therefore help the gods. As a mare, Loki gives birth to the stallion Sleipnir. Loki also sires the wolf Fenrir.
Loki tricks the blind god Hod into shooting Balder with the only entity that hasn't sworn an oath not to hurt Balder; that is, mistletoe. As punishment for his role in the permanent death of Balder, Loki is bound to a jagged cliff until world's end, Ragnarok. Loki is malevolent, cunning, clumsy, magical, and eloquent. He often associates with Thor or Odin.