Online:The Thunder Breaks

Quick Walkthrough
# Talk to Hallfrida.
# Raise banners at the four strategic guard posts.
# Talk to Sergeant Sjarakki at the keep.
# Defeat the invaders in the storage tunnel.
# Talk to Hallfrida.
# Save Thane Unnvald or kill Thorulf.

Detailed Walkthrough
Raise the Banners
Talk to Hallfrida on the second floor of Fullhelm Fort. She will tell you that the fort is being invaded by an unstoppable tide of risen corpses. The dead could keep coming, and they need to be pushed back to reopening the road to Riften from Stonefalls. She tells you four guard posts were lost during the first attack, and that you should take them back to pave the way forward for Fullhelm's soldiers, who have been daunted by the invasion. You've retrieved Bonebane, which they'll recognize upon sight. This will give them hope and the motivation to fight on.

When you go outside, you'll find the place swarmed by the undead. Go to each of the four spots marked on the map. At each post, two guards that die the instant you arrive may be present. Kill the skeletons and raise the banner at each post. Two Fullhelm Soldiers will arrive to protect the post after the banner is raised; after you've reclaimed all four posts, return to the keep.

Defeat the Invaders in the Storage Cellar
When you return to the keep, you'll find that the storage room is on fire. Talk to Sergeant Sjarakki, who will tell you the soldiers set the storage room on fire themselves. Apparently, the undead were entering the keep from a tunnel beneath the storage cellar while they were defending the hall. The fire is keeping them at bay, but it won't last. She'll be elated when you volunteer to enter, and suggests that if you kill enough undead, the Worm Cultist behind the attack may reveal themselves. 

Go into the trapdoor that leads to the storage cellar. You'll come upon a Nordic ruin which has collapsed in the first room. Two guards will follow shortly after you to help. After killing a few waves of undead, Falkyn Milkeye appears. Kill her and leave the cellar.

Save Thane Unnvald or kill Thorulf
Outside, Hallfrida will come out shouting there is something wrong with her grandfather. She'll tell you that while everyone was fending off the dead, Thorulf raised a skeleton in the manor and told Thane Unnvald that they're all going to die. This stirred the old thane into a frenzy, and Hallfrida worries he might kill himself. However, Hallfrida will also tell you Thorulf fled after hearing you were taking care of the undead in the storage cellar. At this point, you need to choose if you want to save Thane Unnvald Ironhand or go after Thorulf. If you save Unnvald, Thorulf will get away. Similarly, if you go after Thorulf, Unnvald will die.


Go into the keep, and you'll find Unnvald hiding upstairs. Talk to him. He tells you that he plans to burn himself to death to prevent the necromancers from raising his corpse. When you try to tell him that it's unnecessary, you'll find that Thorulf's influence on the thane is stronger than you may have thought. Unnvald believes that you're the necromancer, that all his soldiers are dead and the fort is lost. Tell him there is proof that Thorulf is the necromancer instead, and he insists that such a thing is impossible, as Thorulf gave him a token of his faith. As it turns out, this "token" is a shard of Wuuthrad. Thorulf did something to the shard that allowed him to influence the thane's mind. Unnvald will tell you he'll take care of Thorulf, and that Hallfrida will keep the shard safe until you need it again, after which you are given a reward.


Go to the southeast road, where you will find Thorulf. Kill him. Just before he dies, he will shout that he has "waited years to have her", implying that his unrequited love for Hallfrida was part of his motive. When you return to the keep, you'll find that the undead are gone and peace has returned to the fort. Head on inside, and you'll be informed that Hallfrida is now the thane. Tell her Thorulf is dead, and Hallfrida reveals that Thorulf left a shard of Wuuthrad behind in his haste. When you ask if the shard's magic may have been used to weaken Thane Unnvald's mind, Hallfrida doesn't seem to care much for the answer to that. The only thing she knows is that her grandfather died because he listened to Thorulf. Hallfrida vows to keep her grandfather's legacy alive as the new Thane, and tells you that she'll keep the shard of Wuuthrad safe until you need it. She then gives you a reward for saving the fort.
  

Quest Stages