Vader wouldn't need Boba and the Clone troopers (Vader Pre-Obi Wan fight). Vader would force slam the Didact against the wall, knocking the Didact of his feet and stunning him, at the same time Vader uses lightning to fry the promethium knights to a crisp. Vader uses the force to crush the Didacts armour to pieces and then he would use the force to raise the Didact off the floor and bring him closer to him. Vader uses the pain caused by his mothers death to fuel his anger to unleash a wave of dark side energy, it explodes every cell in the Didact's body tearing him from the inside out.