Severus Snape is the Hogwarts Potions Master. He is a half-blood wizard who was a professor at Hogwarts School of Witchcraft and Wizardry and Head of Slytherin House. He is known for his complicated and often antagonistic relationship with Harry Potter. Snape is a master of potions, having studied the subject extensively and being able to brew complex and powerful potions. He is also an expert in the Dark Arts, having studied them extensively and being able to cast powerful spells.