First Appearance: Fantastic Four (vol. 1) #513 (July 2004): "Best Left Forgotten"
Super? (Has Super Powers/Special Abilities/Technology): Yes
Number of Appearances: 1
Note: tentacled creature in ruins of Mayan temple
The Xunanguero may be a degenerate Mayan deity, or it may simply be a monster that happened to be accessed via the ruins of a Mayan temple. Given its name and location, it seems likely that the Xunanguero is tied to ancient Mayan religion and myth in some way.
Suggested links for further research about this character and the character's religious affiliation: