Hydriel is a demon and a wandering duke of the air. Hydriel has 100 great dukes and 200 lesser dukes and their servants beneath him. The 12 chief dukes each have 1,320 servants. All the demons must be summoned according to their appropriate planetary hour. When they appear, each has the form of a serpent with a virgin’s head and face. Unlike the spirits of Buriel, they are courteous and obedient. They prefer to be around water and moist places. The 12 major dukes of Hydriel are Mortoliel, Chamoriel, Pelariel, Musuziel, Lameniel, Barchiel, Samiel, Dusiriel, Camiel, Arbiel, Luciel, and Chariel.