The man started to turn very still at that, and Harry hastened to free him of the railing by commanding the wooden snake, the Dark Lord had charmed to life to return to her place on his bedpost. Snape rubbed his throat compulsively. "I ... I can't see," he whispered. Then louder, "The Dark Lord blinded me." He flinched back violently when the teenager tried to ease him. "I know. He made you a disadvantage. I think he wanted to teach me to prioritise. But it's okay. We'll find a way to end his spell. Finite Incantatem!"