Complex sentence: According to Varney, he was cursed with vampirism after he had betrayed a royalist to Oliver Cromwell and accidentally killed his own son afterwards in a fit of anger, although he "dies" and is revived several times in the course of his career.
Split into simpler sentences: According to Varney, he was cursed with vampirism after he betrayed a royalist to Oliver Cromwell, and subsequently killed his own son accidentally in a fit of anger. He "dies" and is revived several times in the course of his career.