Nagini is a major magical serpent in the Harry Potter series, best known as Lord Voldemort's loyal familiar and one of his Horcruxes. She serves as both a dangerous weapon and a symbol of Voldemort's power, often appearing near him to protect him and attack his enemies. In the Wizarding World, Nagini is feared for her size, intelligence, and deadly venom. Her role becomes especially important in the final conflict, where she is targeted as part of Voldemort's defeat.