In Aztec mythology, the deity who presides over the cycle of life and death is Mictecacihuatl, also known as the Lady of the Dead. She rules the underworld, overseeing the souls of the deceased and ensuring their safe passage. Heavily associated with the Day of the Dead celebrations, she embodies the reverence and recognition the Aztecs gave to life cycles, emphasizing the interconnection between death and existence. Mictecacihuatl's role highlights the cultural importance of honoring ancestors and the spiritual beliefs surrounding rituals in Aztec society.