Alpha

Alpha was the first of the Dark Ancients, who studied Adar psychic powers and used them to free his magical golem soul from his corporeal form. He may or may not have aided the other "normal" Dark Ancients (Beta, Delta and Epsilon) in their ascendance.
According to Epsilon, Alpha is now dead ("he didn't make it"), but Epsilon is not exactly known for his trustworthyness, so he may still be alive out there. Somewhere. Waiting.