I don't recall such a thing from the listing of his arsenal, but does Doug have a song that'll allow him to impose silence on one specific person -- their mouths still move, but no one hears anything? Shutting Umbridge up, not during her speech (when she's entitled to reveal herself as a stupid, totalitarian bigot), but when she wants to interrupt Dumbledore's words with her "Hem, hem," might strike the Loon as an appropriate measure.
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Big Brother is watching you. And damn, you are so bloody BORING.
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Big Brother is watching you. And damn, you are so bloody BORING.