"Yes, exactly, well done Hermione!" she beamed, "Any idea why they stopped teaching it at Hogwarts?" she hesitated, and then shook her head, "It was decided, in the wake of the First World War, that Hogwarts should not be teaching wizarding children magic that was purely offensive, with no other utility. Other spells fell out of favour as well - the slashing curse, the burning curse, and the aptly named eye-exploding curse," more than one person winced, "others that were banned have since worked their way back into the curriculum, such as the blasting curse, but the combat bolt wasn’t one of them. But I’m going to teach it too you," Harry was surprised to find Draco’s hand in the air; he knew for a fact that Unspeakables were trained in the basic combat jinx, "Draco?"