Curse of the Nornbear

Overview
Summary
 * Speak to Sif in Sifhalla to begin the hunt. (disappears from Quest Log after speaking to Sif)
 * Join Jora and Sif. Get the Volfen Blessing from the Shrine of the Wolf Spirit.
 * Invoke the Volfen Blessing to receive the abilities of the wolf spirit.
 * Track down Svanir, the Nornbear.
 * Use the skill Volfen Bloodlust to follow the scent of the Nornbear.
 * Stay on Svanir's trail.
 * Pursue Svanir. Don't let him escape.
 * Slay Svanir, the Nornbear.

Obtained from
 * Automatically added to quest log after completing Tracking the Nornbear
 * After first completion, can be obtained from:
 * Sif Shadowhunter in Sifhalla
 * Scrying Pool in Hall of Monuments (select "I seek guidance" option)

Requirements
 * Tracking the Nornbear

Follow up
 * Flames of the Bear Spirit and Vision of the Raven Spirit (primary quests)
 * Leader of the Pack

Rewards

 * Unlock Hero Jora

Walkthrough
Follow the quest arrow, battling your way through mandragors and jotnar. Once you get to the shrine area, there will be several wolves who will turn from ally to foe and start attacking the jotun. After all foes in the area are cleared out, you can click on the Shrine of the Wolf Spirit and equip the Volfen Blessing skill on your skill bar.

If you activate Volfen Blessing and use Volfen Bloodlust. it will make a quest marker appear, indicating Svanir's location. You will have to track him down three times. In the first two fights, he will disappear after taking some damage. The third time, you will fight him to the death. After the cutscene you will be returned to Sifhalla.

The Nornbear will appear when you reach each location regardless of whether you are actually using Volfen Bloodlust or not, so as long as you know where he will appear (locations 2 through 4 on the map), you do not have to activate the shrine at all.

Hard mode
When combined with the conditions spammed by other mandragors, the Dreamroot Mandragor's Fevered Dreams makes it by far the most dangerous mob in the mission, so it should be targeted first in the mandragor groups.

NPCs

 * Spirit
 * Shrine of the Wolf Spirit
 * Norn
 * 20 Jora
 * 20 Sif Shadowhunter

Monsters

 * Giants
 * 28(30) Jotun Skullsmasher
 * 28(30) Jotun Bloodcurdler
 * 28(30) Jotun Bladeturner
 * 28(30) Jotun Mindbreaker
 * Mandragors
 * 20(26) Mandragor Scavenger
 * 20(26) Ulcerous Mandragor
 * 20(26) Dreamroot Mandragor
 * 20(26) Mystic Mandragor
 * Animal
 * 24(30) Savage Nornbear
 * 20(26) Stonewolf
 * 20(26) Arctic Wolf

Dialogues
Briefing from the Scrying Pool.

Trivia

 * The sword that Jora wields in the final cutscene is not the one she was using during the mission.
 * Jora is an ally during this quest, so bringing her as a hero will not rename her to "Norn Warrior," resulting in two Joras onscreen at once.