During the first part of this battle, use Force Repulse or Force Shield with lightsaber attacks to take him down. When he runs into the room with hot red floors, pull an object off from the wall and hit him with it before he can attack you. After hitting him, Force Dash over to where he is and get some easy hits on him. Once he jumps on to the platform with you, use Force Repulse or Force Shield and maybe some Force Lightning. Try blocking as much as you can; if he hits you, he will do significant damage. Once he is close to being dead, press X to start the button sequence. After a short intermission sequence, you will have to battle him again--this time without his helmet. This battle is simple; just stay out of the air. He will try to use Force Grip on you if you are in the air and he isn't stunned. Use Force Dash to get away from him and use Force Repulse to break his block. Get a few hits in and he will not stand a chance. It will only take a couple Force Repulses to take him out, even under the Sith Master difficulty setting. Do the button sequence to defeat him.