According to imdbKlopf in German means knock. This is used in the same way as in cards, meaning pass.
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Sat 25 Jan 2025, 7:54,
archived)
It's German/Dutch yeah, but the actor literally claims he was saying 'TLER.Maddening.
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brb Monkhouse Stampede,
Sat 25 Jan 2025, 14:54,
archived)