Thomasin's Turn to the Darkness, to Satan, and to Witchcraft
Having killed her mother, Thomasin takes a long nap. She wakes up in the darkness of the next night, and heads to the broken stable to find Black Phillip. Still not sure if he can actually talk, or if his agency was just fantasy on the twins' part, Thomasin asks him to speak. No answer. When she asks him again, though, he responds in a deep, gravelly voice, asking what she wants. He asks if she wants all the happiness and riches and spoils of the world. She says yes.
We suddenly see the legs of a man who walks behind her. This, unmistakably, is Satan himself. He puts his hand on Thomasin's shoulder and binds her by contract. She removes her clothes. He leads her into the forest, where she happens upon a huge bonfire. A group of naked women dances around. They suddenly all begin to levitate, and a tight shot on Thomasin's face shows that she's levitating, too. The screen cuts to black.