The promotion to Master-Wizard requires you to complete two quests – “The Bloodworm Helm” and “The Necromancer’s Amulet”. Both of these quests are given to you at the same time and it doesn’t matter in what order you complete them.
The Bloodworm Helm – Simply travel to Fort Teleman to the northeast of Leyawiin and fight your way through the necromancers that you find there. You’ll eventually find a group of necromancers fighting Daedra. Let them kill each other and then finish off the survivors. At the end of the fort, you’ll find the body of Irlav Jarol. Take the Bloodworm Helm off of his corpse. If this is the first quest you’ve done, proceed on to “The Necromancer’s Amulet”. If you’ve done both, return to Traven and then speak to Raminus to receive your promotion.
The Necromancer’s Amulet – Travel to Fort Ontus, northwest of Skingrad, and talk to the mages inside the fort. They will direct you to Caranya. Talk to her until she reveals that she is a necromancer. At this point, she will attack you. Once she’s dead, take the Necromancer’s Amulet off of her body. Be careful as you exit the fort because the mages will not attack you. If this is the first quest you’ve done, proceed on to “The Bloodworm Helm”. If you’ve done both, return to Traven and then speak to Raminus to receive your promotion.