Wanülü (wanülüü) is the Wayuu being of supernatural sickness and death. When ordinary plant and fire remedies fail, an illness is classed as 'of the wanuluu type', its cause traced to this malevolent agency rather than to natural disease. In the cosmological scheme recorded by Perrin the wanulu is the most dangerous messenger of Pulowi: a being who takes the appearance of a man and is sent by her to gather the blood and lives of human beings, including women whom he approaches and sickens. He thus belongs to the dark, death-dealing pole of Wayuu cosmology presided over by Pulowi, opposite the life-giving rain of Juya, and is the principal supernatural explanation the Wayuu give for fatal and intractable disease.