The key to success during the first phase of the fight against Dravakar is to clear out zombies while Tyr weakens him, then when one of Dravakar's weak points is exposed, deal as much damage as possible to that point knocking him down. This is the goal throughout the entire first phase. In the second and final phase of this fight, you will need to hide behind rocks to avoid his Ice Rock Barrage attacks, and move around the arena to be out of range of his Frozen Dawn attack, covering 1/3 if not more in ice.

For weapons, you'll want something long ranged to be able to deal sufficient damage to his weak points, while you are behind cover as he always stays quite far from the arena. You can find a list of recommended weapons, along with a full detailed guide with images in our Totenreich Main Quest Guide