Harry spotted Charlie at the centre of the three broom-mounted wizards as soon as he was floating above him. The temptation to crash a fierce spell into his face was borderline overwhelming, but Harry held himself steady. Then he held his broom vertical a moment, before rocketing upwards like an invisible dart, piercing straight though the middle of the circle the Death Eaters had formed. The shock wave caused by his rapid passing was powerful enough to send the other brooms all spinning away as if caught in a sudden gale.