Magnus is an ancient and illusive sorcerer. He considered himself the be the arch-enemy of Morgan le Fay. He was in possession of a magic book, he stole from le Fay, which contained powerful black arts sorcery.
Magnus is an centuries old human magic user, capable of performing impressive spells.
Illusions: He is able to create powerful illusions, that is able to fool anyone around them. He used an illusion spell in order to turn an clothing store in his own magic shop and present himself as a innocuous tarot reader to Jessica Drew. 
Magnus existed in astral form for about 14 centuries.