If you’re planning to use the Greatsword in The First Berserker: Khazan,my personal recommendation for best build utilizes the Fugitive Mage set. This is an eight-piece set with some of the best Greatsword buffs available in the game. You’ll want to invest heavily into Strength and Proficiency for the ultimate Greatsword build, but don’t sleep on Vitality and Endurance either, as the Greatsword can sometimes be slower than the other two weapons in The First Berserker: Khazan.