While it can account for both age and gender, Polyjuice Potion cannot be used for a human to take an animal form, nor can it be used on non-humans or half-humans. Noticeably, the Polyjuice Potion was used many times in the events leading up to, and during, the Second Wizarding War (and possibly the First Wizarding War, although there are no documented instances of it). The potion also played a crucial role in Harry Potter, Hermione Granger, and Ron Weasley in their second and fourth year. It was also used in Draco Malfoy's plot to smuggle Death Eaters into Hogwarts School of Witchcraft and Wizardry in 1997, in the Battle of the Seven Potters, and in Harry, Ron and Hermione's Infiltration of the Ministry of Magic and their break-in of Gringotts Wizarding Bank in 1998.