Ron pulled out his own wand -- not knowing what he was going to do he heard himself cry the first spell that came into his head: "Wingardium Leviosa!"
The club flew suddenly out of the troll's hand, rose high, high up into the air, turned slowly over -- and dropped, with a sickening crack, onto its owner's head. The troll swayed on the spot and then fell flat on its face, with a thud that made the whole room tremble.

Harry Potter and the Philosopher's Stone - Chapter 10 : Halloween
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