Adar was one of the first elves (if not the first) whom Morgoth perverted in the dungeons of Utumno back in the Years of the Ancients to create a new race, the Orcs. Subsequent generations of Orcs considered Adar their father and willingly followed him. After Morgoth's defeat, Adar first served Sauron for his purposes, to find a way to conquer other life forms. However, disappointed by Sauron's cruelty towards the orcs, Adar turned against Sauron and claimed to have killed him.