X'tabay is a character in Guacamelee! She is the ex-girlfriend of Carlos Calaca. She is a supernatural-powered woman who becomes jealous when Carlos starts spending time with El Presidente's daughter instead of her. X'tabay is also encountered in the Temple of Rain, and is responsible for taking care of Carlos' pet Alebrije. When the pet is destroyed, Carlos blames her and tells her to go back to her lair until she is needed. Juan finds her, and they battle. After her defeat, she grants Juan the Dimension Swap ability and decides to break up with Carlos. Defeating her grants the "X'tabay-bye trophy."
X'tabay's lair is in the dead world beneath Pueblucho. The hut through which it is accessed is decrepit in the living world. A townswoman explains that this is because no one has lived in the hut for a very long time: people refuse to because it is said it used to be the home of a witch. This witch is presumably X'tabay, although the time of her residence is unclear.
Where Calaca and most dead denizens are skeletal, X'tabay is not. It is possible she actually isn't dead, herself, but has simply prolonged her lifespan through her supernatural ability and free reign of world crossing. Though her abilities in battle revolve mostly around poison vapors, rain, and bugs, it is with her help that El Diablo is polymorphed suggesting a much broader array of abilities.
After her defeat, she ditches Calaca and expresses an interest in Fray Ayayay. In the credits she can be seen mingling with Juan alongside Fray Ayayay, suggesting she did indeed enter into a relationship with him.
After defeat her,in the brazillian portuguese,you receive an achievement called "X'tabay Do 71", and its a reference to El Chavo Del Ocho