It is nice to have someone clear up history because although it remains in the folklore that Aurangzeb was very cruel, the school textbooks seldom mention his misdeeds. He did not just kill Dara Shikoh, the heir to the throne, but also his two other brothers. The mughal empire had reached its zenith at that time because of the good work of his predecessors: Akbar the Great and Shahjahan. And because of his tyranny and foolishness, the mughal empire declined after him and eventually passed into British hands.