Start Location: Thane in Tri-Stone
Simply challenge Thane to a duel and win to complete this side-quest. He will then give you another four side-quests to deal with some boss monsters in the Forge Lands and The Kingdom of the Dead.
*- Find & Kill Gorewood
Find & Kill Bheithir
Find & Kill The Deposed King
Find & Kill Achidna*
Side Mission: The Maker Warrior
The main thing to remember in this fight is that you don't have to get rid of all of Thane's health. As long as you clear two-thirds of it, you'll succeed. To beat him, you're best learning the free move he teaches you, then get into the habit of evading an attack and immedately dashing back in to him and hitting attack. This'll activate the new move, then follow up with several secondary weapon moves (ideally you'll already be using something like an axe).
Be careful when you see Thane's main move change to lifting his weapon above his head. This is your signal to evade left or right and you'll need to repeat this a maximum of four times before he returns to his 'regular blade attack'. Thane will now alternate each move between regular and ground slam attacks, so you can plan in advance for this and dodge his attacks much more effectively. Check out our video of this strategy in action above...