Mardero is the demon of fevers. He appears as a man with the shapeless head of a dog and the face of a bird, donkey, or ox. This demon, who causes incurable fevers, was condemned to heavy labor tending the furnaces used for metal-working on the Temple of Solomon. To save a person who has been assaulted by this demon, write the words "Sphener Rafael retire drag me not about flay me not" and wear it around the neck. His personal adversary is the angel Sphener.