Taranushi was the name of the first great djinn. Before the advent of the six tribes, he controlled all the djinn. However in his time he was overthrown by a wicked djinn known as Azazal and was defeated. The Marid tradition that comes from it commemorates his overthrow by wicked djinn.
Because of his kind nature, he tried to improve the lives of human beings by occasionally giving them three wishes. This was the origin of the custom which giving three wishes in the first place.