It is one of two side quests that involves the Thirsk Mead Hall , the other being Retaking Thirsk . This quest will be marked as failed if Retaking Thirsk is accepted.
This quest can be started by approaching the entrance to Thirsk Mead Hall . A Riekling will initiate dialogue and ask the Dragonborn to follow him inside. Once inside speak to the Riekling Chief . Incredibly, he has learnt how to speak and explains that he has a few tasks that he needs help with.
The first task the chief asks is to find Bilgemuck , a unique Bristleback , and bring him back to Thirsk. Approach the beast and offer it some meat for bait, such as Horker Meat , and it will begin to follow. Lead it to a small pen by the side of the mead hall to complete this errand.
Collect 10 Scathecraw
Next he requires ten samples of Scathecraw , which he calls "redgrass". Scathecraw can be found all over the island or sold by alchemists. Raven Rock also has a great abundance of them.
Kill the Nords
For the final task he will ask the Dragonborn to help him kill some nearby Nords that have been troubling them. If Bujold's Retreat has been visited before, it is revealed that these Nords are actually the previous inhabitants of Thirsk Mead Hall that were driven off by the chief and his soldiers.
Accepting to help the chief will cause him to jump out his throne and run outside, ready to fight. Alternately, the Dragonborn can also voice their reluctance, resulting in the chief waiting inside the hall for the Dragonborn to return later. This gives the Dragonborn the opportunity to talk to Bujold and help her instead.
When the Dragonborn agrees to help Bujold, The Chief of Thirsk Hall quest will fail and the Dragonborn can participate in retaking Thirsk Hall instead.
Usurp the Throne
Once all the Nords have been killed, the chief will mention that the Dragonborn is too strong and perhaps wishes to usurp him, much like he did with the previous chief of the tribe. Next he will attack. Once he is dead the Rieklings of Thirsk will recognize the Dragonborn as the new chief and the quest is completed.