Xibalba is as old and ancient as his wife, La Muerte. His flesh is made completely and entirely out of black tar, with green eyes and blood-red skulls for pupils. He has a pair of large, black raven angel wings, and is the only known ancient, immortal god to have them. He wears a regal black cloak covered by conquistador chest armor, black gloves with teal flames, and a silver crown with horns sprouting from the both sides, topped with black wax candles lit with green flames. When assuming a mortal disguise he tends to take on the mortal form of an elderly, old mortal man. Xibalba has a very handsome white mustache and white beard. Xibalba fingers are long and spindly an razor-sharp an clawed.
Xibalba is a very sly, very clever, very cunning, cruel, very charming, somewhat suave, highly manipulative, very persuasive, cheating and lying ancient, immortal god of death, decay, manipulation, trickery, tar and darkness. He truly thinks and truly believes the heart of mortal, humankind is impure and not-so-true, sinful and full of sin, and beyond redemption like himself. He is quite selfish, as seen when he used his double-headed snake staff to kill Manolo so he could win the wager with his wife La Muerte. Xibalba is also a troublemaking trickster an troublemaker and mischief maker who loves tricking mortals into making sophistic deals with him. He also loves meddling in the lives and affairs of mortal, humankind and mortal beings because it is the only fun and enjoyment he ever gets, as a result of his punishment for having cheated in a past wager with his wife La Muerte. But despite his very fearsome, very infamous, very notorious reputation, Xibalba is more mischievous and amoral than he is evil. He comes across as fearsome and heartless, but there is also a sweet, kind, tender, very loving, very caring, compassionate side to him that he only ever shows to his wife La Muerte. Xibalba is also a silver tongued smooth talker. Xibalba has a truly pessimistic, truly negative view of mortal, humankind and mortal beings but despite his beliefs and views of mortal, humankind and mortal beings Xibalba still has a admittedly grudging respect for some certain individual mortal beings like Manolo Sanchez. Xibalba can also be impressed by some certain individual mortal beings if the mortal beings leave a good enough impression for him.