Magician

The magician is a character in the backstory of Zelda II: The Adventure of Link. He does not appear in the game, and is only mentioned in the manual.

Zelda II: The Adventure of Link
The Magician was a sorcerer who was close to the king of Hyrule and a close confidant of the crown prince. He brought the crown-prince unexpected news about the king and the prince's younger sister, princess Zelda. When the magician and prince questioned the princess about the Triforce, he had lost his temper after awhile and threatened to put her into an eternal sleep. She still refused to talk and with his anger, the magician tried to cast a spell on her. The prince was surprised and tried to stop him, but the wizard fought off the prince and chanted the spell. The sorcerer died when Princess Zelda fell to an eternal slumber which can only be broken by uniting the Triforce.

Appearance
He features many wrinkles, has light blue skin, red eyes and long fingernails which are white. He wears a purple robe with a necklace, which seems to resemble the Great Demon King Ganon. He bears a striking resemblance to Carock, the enemy of the Maze Island Palace.

Origin
Hyrule Historia proposes that he could be an offshoot of Ganon's, similarly to Agahnim. However, it also mentions that he could just be another follower of the Great Demon King.