Lord Voldemort from J.K. Rowling's Harry Potter series needs no introduction. Perhaps he, more than any other villain I've talked about or will talk about, was written in an almost a perfect parallel with the hero.
Villains make heroes/heroines--driving them to find more courage, more ingenuity and just being more than they could ever imagine possible.
The similarities between Voldemort and Harry scare Harry, who wonders at various times throughout the seven books (eight movies), if he will fall to the same evil. The beauty of this set of books is the reminder of how the choices the we make throughout our lives, even when facing the same set of challenges, or possessing the same set of assets (or weaknesses) determines the road we travel and the people we become.
Often, it seems, its not just that the villain makes the hero, but in other circumstances, the villain perhaps could have been the here. Equally, our protagonist, but for a choice here or a choice there, could be the antagonist.
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