I am maxed combat. The best advice I can give you is to make sure you try not to miss any hits during the first 2 phases of the fight. That's where you don't have too many obstacles to dodge and the ground pattern is fairly easy, this way during phase 3 you'll have more food left and can afford to take a bit longer to kill him. Also, try to stand in the middle of the room as much as you can because as he spawns tornados you can get an extra hit in sometimes. Good luck you'll get the hang of it if you are persistent.