I Spit on Your Grave (1978)
Ah, the much-maligned rape-revenge genre. You knew some of these films had to make it onto a list of the most violent horror films, didn’t you? Well I Spit on Your Grave is generally considered the most morally odious entry in the genre. Roger Ebert famously called it ‘a vile bag of garbage’, which most horror fans take as a mark of quality.