Mask of Mictlantecuhtli: A 500-year-old mask of the Aztec god of the underworld, who tore apart the dead as they entered his realm Live Science By: kkillgrove@livescience.com (Kristina Killgrove) 15 June 2026 at 11:00 This skull-shaped mask was made to be used in a ritual involving the Aztec god of death.