An Island of Eels

After The Stench of Treachery, regroup with Soma and her clan in a camp northeast of Grantebridge (northwest of Isle of Ely Monastery). Speak with Soma to proceed.

Head southeast towards Ely Monastery. Raid the monastery by killing all enemies and looting all items. Use Odin's Vision to spot archers on the walls and take them out. Be aware of Yeomen, who are tougher enemies; use heavy attacks and well-timed blocks/parries.

Inside the monastery, loot a chest on the second level of a building to the southwest.

Continue south to another large building containing a large treasure chest of Raw Materials. Summon your crew to help open it. Move the structure blocking access or climb over it.

Head back outside and north down the steps. Enter the building on your right to find more Raw Materials, using Odin's Vision to locate them.

Continue northeast to the cloister. Use Odin's Vision to highlight treasure in the building northeast of it. You'll need Soma or a crew member to open the door.

Wigmund will charge you. While Soma will focus on him, you need to confirm the kill after he is defeated.

After the cutscene triggered by Wigmund's defeat, loot another chest filled with Raw Materials at the northern end of the room.

The raid is not quite complete. Find a secret passage on the shore to the east to access the area beneath the cloister. Pick up Opal in the cave before the first doorway.

Follow the linear path to find a Book of Knowledge containing the 'Dive of the Valkyries' melee ability.

Return to the camp in the northwest. Enter the camp for a cutscene and dialogue options. These choices do not have a significant impact.

If you accused the correct traitor in the previous quest, you will have a scene with Birna, who may ask to join your crew. The quest ends after this conversation.