Ixtab had taken over Shibuya's Underground Shelter in Blasted Tokyo years ago, killing everyone there so they can live as ghosts in what she considers to be paradise. She has created a Domain on the bottom floor and is found at the end of it. To her the most unfortunate things about humans is their birth, so she shall lead them to paradise whether it be willingly or not, where they will be free of God's control.
Ixtab then summons the Bound Horde to start the battle, appearing after their defeat. Upon defeat, she is shocked that they reject their salvation as her body starts to crumble, as she is unable to comprehend why they would want to live in the wasteland of pain and suffering when they can live in the paradise of death. Her final words is that they will come to regret it. The souls she killed linger after her death, but are slowly fading away.
"The Mayan goddess of suicide. Portrayed as a woman hanging by the neck from a rope, her figure is that of a hanged corpse. Despite being a death goddess, she was worshiped by many. This is because she was the guide for souls who died by suicide, sacrifice, war, and childbirth. She also guided deceased members of the priesthood. She took them to rest under the shade of Yaxche, where they would enjoy a life of luxury."