Wizards didn't kill ordinary people because a) they seldom noticed them and b) it wasn't considered sporting… — Terry Pratchett

Wizards didn't kill ordinary people because a) they seldom noticed them and b) it wasn't considered sporting and c) besides, who'd do all the cooking and growing food and things. And killing a brother wizard with magic was nigh-well impossible on account of the layers of protective spells that any cautious wizard maintained about his person at all times.*

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