Not with standing the similarity of the concepts of night, earth, and death, as opposed to those of light, sky, and life, there were special deities who held dominion over the underworld, which the Aztecs thought of as the dwelling place of those who had died. It was called Mictlan, the place where Mictlantecuhtli, "the lord of the dead," ruled.
The god is portrayed with his body covered with human bones. Over his face he wears a mask in the form of a human skull. His hair is black, curled, and studded with starlike eyes, since he dwells in a region of utter darkness. He wears paper ornaments in the form of rosettes, with cones protruding from the center; one is worn over the forehead, the other on the back of the neck. They are called ixcochtechimalli and cuechcochtechimdli respectively and are typical of his attire. He uses a human bone as an earplug. Animals associated with him are the bat, the spider, and the owl (tecolotl), a bird of ill omen whose nocturnal song is considered even today to be fatal to anyone who hears it.