You need to make your way to Glacial Cave in the northern part of the map and then after killing the three Rieklings inside, pick up the [ Karstaag’s Skull ] from the ice wall at the back. Now it’s time to head to Karstaag’s throne of which there’s two ways to reach it.

The first route requires you to head to Castle Karstaag Ruins and pick the master-level lock here (so save right before you attempt it, giving you infinite attempts). The second - and longer - route is through the Castle Kaarstag Caverns .

It’s jammed packed with Rieklings, so take your time (and you can also complete the other side-mission Recover the Bonemold Formula for Glover Mallory whilst you’re down here). You’ll soon reach the throne room (where the picked lock option takes you). Place the mask on the skeleton of Kaartag and then move away as the boss battle will begin!

Boss Fight

It’s worth noting straight away that this boss will deal very high levels of ice damage to you and it is itself resistant to ice, poison and disease attacks (so don’t even bother trying). It’s a good idea to leave this quest until near the end as you will ideally want to be armed with loads of Black Book spells.

Companions will generally go down quickly too, so you’ll want to be packed up with loads of ice resist potions. Fire mages can do well, as too can those with very high sneak attributes.

Once the boss is defeated, you’ll recieve the power to summon Kaarstag for a total of three times . He’ll join you in any outdoor battle you require for 120 seconds (and will likely make it an insta-win too), but once you’ve called him for the third time, you can’t call him anymore.


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Guide Information

  • Publisher
    Bethesda Softworks
  • Platforms
    PC, PS3, PS4, Switch, XB 360, XB One
  • Genre
    Action RPG
  • Guide Release
    31 May 2012
  • Last Updated
    19 October 2021
    Version History
  • Guide Author
    Greg Wright

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Skyrim is the homeland of the Nords, a fierce and proud warrior people who are used to the bitter cold and mountanous terrain that mark the lands of Skyrim. Wracked by civil war, and threatened by the return of the legendary dragons, Skyrim faces its darkest hour. You must make sense of this maelstrom, explore the frozen tundra and bring hope to the people. The future of Skyrim, even the Empire itself, hangs in the balance as they wait for the prophesized Dragonborn to come; a hero born with the power of The Voice, and the only one who can stand amongst the dragons. You are that Dragonborn.

Version 1.2

  • Introduction to the Races.
  • How to complete every storyline quest.
  • Where to find and conquer every side-mission.
  • Location of every powerful Dragonwall.
  • Search out and defeat every Dragon.
  • How to find hidden, powerful weapons.
  • Over 200 captioned screenshots provide even more help.
  • Dragonborn DLC covered in full.
  • Dawnguard DLC covered in full.
  • Screenshots for the major side-missions.
  • Achievements/Trophy descriptions (includes all 3 DLC packs).
  • Character Creation guide.

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