Sexual Experiences of a Horse(1985)

Original title: Experiências Sexuais de Um Cavalo

Kamoa, a civilized Indian, has his house invaded by malefactors who kill his wife and rape his sister-in-law. Revolted, the Indian returns to his origins and begins an impossible revenge, in which he rapes the malefactors' wives in their presence and kills each with seven different deaths. That is, seven Indian deaths.