Saruman the White (Earth-1943)

"There is only one Lord of the Ring, only one who can bend it to his will, and he does not share power. Concealed within his fortress, the lord of Mordor sees all. His gaze pierces cloud, shadow, earth, and flesh. You know of what I speak, Gandalf: a great Eye, lidless, wreathed in flame."

- - Saruman to Gandalf the Grey

Saruman the White was an Istar that acted as the leader of all wizards in the White Council, the front line leaders that knew of Sauron's imminent return. His studies of dark magic, however, led him to want the One Ring to himself, and for this end he joined Sauron in the hopes of betraying him later on, using the dark lord's own creation against him. At the side of Mordor during the coming War of the Ring, Saruman tutored Lord Petyr Baelish, who helped to destabilize the Seven Kingdoms by inciting the death of King Robert Baratheon and eventually spark the War of the Five Kings.