Ayauhtéotl

 is a minor character featured in the Red Dead Redemption Undead Nightmare DLC pack. While omnipresent throughout the game, she is specifically encountered during the mission "A Civilized Man".

Background
Ayauhtéotl was the Aztec being, force or Goddess who controlled mist, smoke and most particularly Crepuscular rays, the dark and light beams that appear under the right condition at sunset. She was also the Goddess of fame and glory. (Info from: ) It appears that when Abraham Reyes stole a sacred artifact, in this case the Mask, she became human to retrieve it. The mask was cursed, reanimating the dead and a magical plague with them. It seems that she can disappear when she is in god-form. She has the ability to command the Death Horse and lift the plague once her power is restored. Yet, in human form, it appears that she is mortal, and fears being killed by the Undead Reyes.

Interactions
She first appears as a woman that is in both groups of survivors in Blackwater, then again with the Sasquatch Hunter. She also appears in the opening cutscene of the survivor mission "Dinner for Two". She later is seen in the opening cutscene of the "Missing Souls" mission. After John Marston meets Mother Superior, she again appears as a nun. Mother Superior tells him that the nun had told her that the curse was caused by Abraham Reyes, who disturbed an Aztec crypt.

When John tracks Reyes down, he finds the zombie Reyes chasing this same woman around a table. After Reyes is dispatched, she shows John the Mask that Reyes took. Whilst taking him down to the crypt, her behavior becomes increasingly unusual, mentioning the zombies' anger and ancient curses while John notices that the Undead aren't attacking her. Much to John's surprise, she also quotes Jack on the story that he was reading: "Some people worshipped the moon, and the brave man has to kill everyone...". Upon reaching the Altar, she tells John to return the Mask and disappears as he does so. She says her name is  and a horse is waiting for him outside so he can return home. John Marston stood for a moment, confused of what happened. The horse is Death, one of the Four Horses of the Apocalypse.

Trivia

 * She may be able to become invisible from some people's sight, or make them ignorant of her presence as, in Blackwater she is seen with multiple survivors that don't seem to notice her at all, however the Sasquatch Hunter can see her, and claims to have rescued her from a sasquatch.
 * She may be able to create fake humans or hypnotize people, as when she was rescued, her family met her.
 * If the player attempts to re-enter his house at Beecher's Hope before completing the game, a small cutscene will play that shows Marston decide against opening the door when he hears 's voice ask: "Did you listen to a word I said?" The cutscene in question can be viewed in this video at the 8:05 mark. This happens even if she has yet to be encountered.
 * The player can kill her after her second appearance in "Curious Tales from Blackwater, USA" in the same fashion as Bonnie MacFarlane after the Hanging Bonnie MacFarlane mission, by shooting your shotgun just directly to the left or right of her head.
 * If the player climbs to the roof top of the building with the first group of survivors in the above mission then she will not appear with the family like she does in the cutscene.
 * Although Ayauhtéotl is an Aztec goddess, the mask appears to resemble the Were-Jaguar figures of the Olmec culture more closely than any Aztec artifacts.
 * Her mask is the treasure that Basilio Aguirre Olmos de la Vargas talks about. If you remember the map it fits the tunnels under Escalera that leads to the mask. Another back up to this is that it is both about aztec treasure/the mask.

Gallery
Ayauhtéotl