In Aztec and Toltec mythology, Xolotl ("The Animal", Lord of the Evening Star, Lord of the Underworld) was the god of lightning and a psychopomp, which is to say that he was the one who aided the dead on their journey to Mictlan, the afterlife.

Xolotl was also the god of fire and of bad luck. He was the twin of Quetzalcoatl, the pair being sons of the virgin Coatlicue, and was the evil personification of Venus, the evening star. He guarded the sun when it went through the underworld at night. He also brought forth humankind and fire from the underworld.