When he sees Professor Rammsteiner tense, some instinct tells him that something is about to happen.

It still doesn't prepare him for the feeling of being suddenly shoved back by an invisible force, his back slamming against the wall. It sends a jolt of pain through his already sore body, and he lets out a low grunt.

Then his wand is up and raised, hurling a stunning spell at Professor Rammsteiner.