Lord Voldemort is a sobriquet for Tom Marvolo Riddle, a character and the main antagonist in J. K. Rowling's series of Harry Potter novels.
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Simply put, a horcrux is a piece of one's soul. If a witch or wizard creates a horcrux, then they can never truly die until said horcrux is destroyed as well. A person's physical body can be destroyed, but their soul can live on.
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Harry Potter and The Chamber of Secrets (Second movie and book)
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