Liberation or Apprehension?
Traven tells you that he's got someone working on the inside of this Necromancer cult, but is afraid they are in danger and wants you to rescue him to safely. He dispatches a group of Battlemages and tells you where to meet up with them.
Go south-west of the Imperial City to find Nenyond Twyll. As you walk toward the ruins you are approached by one of the Battlemage. He says the traitor told the Necromancers they were incoming and also that the necromancers killed the others and retreated deeper in.
In a humorous moment, Fithragaer runs straight in with no regard for traps and gets himself killed. Kill the necromancer near the stairs and head north-east. Two more Necromancer's will approach in the large room, kill them and head south-east and enter the door deeper into the ruins.
Kill any necromancer and continue onto the area with the red crystals. Dive in the water to swim under the detection of the red crystals. Kill or sneak passed the undead, and necromancers on the bridge and advance north. Defeat the necromancer blocking the button on the wall and push it.
A secret area reveals itself and Mucianus Alias comes wandering out, as a zombie! Flee the ruins for the Arcane University and tell Arch-Mage Traven. Speak with Raminus about advancement to get promoted to Warlock.
Information at a Price
Traven has informed you that the Count of Skingrad has information he wants to share with you. Go to Castle Skingrad and inside find Hal-Liurz, she will go get the Count. Count Janus wants you to fulfill a duty for him before he reveals his information. Vampires begun to gather in the Bloodcrust Cavern just outside of town, and in turn has drawn the attention of some Vampire Hunters. Being a vampire, the Count wishes you to remove both parties from the region.
Find the Vampire Hunters. The lesser hunters were told not to converse with anyone, so locate the head hunter. Find Eridor, the head Hunter, outside the chapel or at the Two Sisters Lodge. Tell of the vampires in Bloodcrust Cave and they will head out there and attempt to kill them all.
You won't know the outcome of the fight if you let the hunters go into the caves unless you go in, or wait for the end of the day. If the hunters do kill the vampires, they will depart from the city when the finish. If not, you have to go finish off the vampires yourself. When all are gone go back to the Castle, talk to Hal-Liurz and she'll get the Count again. Janus tells you of a powerful necromancer named Mannimarco returning to Cyrodiil in the north-lands somewhere and some of the mages guild have defected.
Back at the Arcane University seek out Arch-Mage Traven of the new info. He shifts his focus to the Mages Council for discussion on the topic and thanks you for the info.
A Plot Revealed
Hannibal Traven asks you to go to Bruma and speak to Jeanne Frasoric at the Mages Guild as he hasn't heard from her recently.
When you step inside the guild building, you'll find that it has been attacked and left to burn. Your job now is to look for survivors. Head downstairs initially, fending off the undead as you go. If you find the undead tricky to deal with, lure them outside to get some help from the guards and local citizenry. Eventually you will work your way to a necromancer who has remained behind. Kill her to reveal the sole survivor of the Bruma Guild massacre and hear what he has to say about the King of Worms.
Once you've got J'Skar's information, head back to Hannibal Traven to give him the bad news. After three days to think about things he will ask you to get the Bloodworm Helm and the Necromancer's Amulet, quests 4.4.1 and 4.4.2 below. You can get the items in either order. Speak with Raminus to advance your rank to Wizard.
The Bloodworm Helm and the Necromancer's Amulet
The Bloodworm Helm
Go to Fort Teleman and fight your way through the first level which is full of Necromancers. Enter the Order of the Black Rose area. Here there are both Necromancers and Daedra fighting each other. If you can keep out of the way they will make your job easier by killing each other, allowing you to cut a swathe through the winners (probably the Daedra). It's all too late for Irlav Jarol who took the helm. Pry it from his cold dead fingers and exit Fort Teleman.
Either return to Traven or get the Necromancer's Amulet if you don't have it yet.
The Necromancer's Amulet
Travel to Fort Ontus. Once inside the fort, any of the mages you speak to will tell you to see Caranya. Find Caranya in the fort understreets (use the lever to open the gate to the room she's in) and talk to her.
Alas Caranya is a traitor and planning to give the amulet to the King of Worms. So kill her and take the amulet. She uses a lot of heal spells so you might like to try a magica draining effect on her to shorten the fight. The amulet is a decent item, but you don't get to keep it if you want to finish the guild quests.
All the mages you passed on the way in are necromancers. So once you have the amulet fight your way out and either take it to Traven, or go and get the Bloodworm Helm as preferred. Once both objects are delivered to Hannibal Traven you will get promoted to Master-Wizard.
Your penultimate task for the guild is to acquire a black soul gem needed to defeat the King of Worms. After getting the quest, travel to the Ruins of Silorn to lead some battle mages in an attack. Unfortunately the enemy have barricaded themselves behind a sealed door, so you'll have to wait for them to emerge. Direct your troops to their ambush positions and shortly afterwards the necromancers will emerge, led by Falcar. The battle mages can take care of them quite easily.
- NOTE: The Battlemages are very sensitive to stray blows and will turn on you quite easily, so be careful how you swing! Yield is your friend.
If Falcar, makes it back inside Silorn you will have to trek through the ruins to find him. The dungeon is large and has plenty of Necromancers. Detour through Silorn Sedorseli to hit the switch which opens the gates keeping you from Falcar in the Silorn Buroseli area
Once Falcar is dead, get the gem, take the shortcut out, and return to Traven.
Confront the King
Once Arch-Mage Traven concludes the Black Soul Gem was meant for him he devises a plan to knock out Mannimarco for good. Go to Mannimarco with the Black Soul Gem and kill him. Traven says you are the new Arch-Mage and then suicides to be put into the Colossal Black Soul Gem. Grab the Filled Colossal Black Soul Gem and head to Bruma.
You can talk to the necromancer on guard of the door, he will tell you he is guarding the cave with his life and begin to attack, so don't bother talking to him. Kill him off and take the key he held to gain access to the cave. Kill or sneak by the Necromancer and undead the first large room and then head north. In the next room will have to succeed two more Necromancers and an undead in the room after that. Head south through the tunnels which leads you to a door leading down to the Echo Passages. Continue to kill or sneak by any more enemies you encounter on your way through.
Save and enter the Echo Necromancer's Charmer, killing the necromancer guarding the path to Mannimarco. Cross the bridge and talk to Mannimarco. His spell doesn't hurt you if you remembered to grab the Colossal Black Soul Gem with Traven inside. Kill him off and loot the area. Head back to the Arcane University and let the Mage's know who is the new boss.
After receiving recognition from Raminus as the new Arch-Mage he tells you that Julienne Fanis has collected Alchemical ingredients for Arch-Mage Traven when he was around and that she may do the same for you. Follow the quest marker to Julienne, she shouldn't be far.
Julienne informs you on how to use the enchanted chest in the Arch-Mages room. Place an ingredient in it, wait 24 hours and retrieve the ingredients out of the chest. Placing any other items or Niroot will result in a lost item.