Goals are scored by chucking a smaller ball (the Quaffle) through one of the opponents three goals without being knocked off your broom by a defense whose job it is to hit a large iron ball (the Bludger) into your body at bone-breaking speeds. The game only ends when a tiny, winged ball with a mind of its own (the Snitch) is captured by a member of either team. Catching the snitch is worth 150 points, regular goals are worth 10. Whoever has more points when the snitch is caught, wins.
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