Fenrir Greyback

Fenrir Greyback (c. 1945) is a werewolf infamous for his brutal savagery and preference for attacking children. He is a leader in his community and strived to infect as many people as possible with lycanthropy, hoping to build an army strong enough to eventually overthrow the wizarding community. 
Following the Second Wizarding War and his escape from Azkaban, he has become more of a pedophile, attacking underage witches and wizards, exponentially increasing the severity of his attacks over time. Eventually, he was exposed to the wizarding community in 2015 by a first-year who witnessed one of Greyback's depraved acts on minors, and alongside the rebirth of the Dark Lord, sparking the Third Wizarding War. 
During the Third Wizarding War, Greyback has created an extremist hate group known as the Terror Five, responsible for attacking and the torture of muggle-born students, especially at Hogwarts and Beauxbatons, using Amycus Faucci's antics as the basis of these crimes. 
He was later captured by the Order of the Phoenix in December 2019 and was locked up in Nurmengard for a year and a half before escaping on August 15, 2021, and has continued to attack minors in wizarding schools, forcing classes to be held online and/or students sent home. By January 2022, Greyback is confirmed by the British Minister for Magic, Hermione Granger to be behind the events that had happened on June 15.