This chapter presents major scholarly typologies of genocide and applies them to the World of Harry Potter. It first explains how genocide scholars classify different forms of genocide—such as cultural, retributive, utilitarian, ideological, and optimal—drawing on the work of Dadrian, Fein, Kuper, Jonassohn and Chalk, and Smith. Despite differing frameworks, these typologies share core themes: domination by a powerful group, punishment of perceived threats, pursuit of security or progress, and the central role of ideology. The chapter then focuses on ideological genocide, emphasizing exclusionary ideologies that define certain groups as inherently dangerous and outside the “universe of obligation.” Dehumanization and toxification are shown to be key mechanisms that enable violence. These concepts are applied to the World of Harry Potter, particularly anti-Muggle and anti-Muggle-born beliefs. Finally, the chapter explores participation, resistance, and rescue, showing how belief, fear, coercion, and moral conflict shape individual behavior within genocidal systems.