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Yeah, touchless knocking would be a bit redundant seeing as how that's basically what Grand Knocking is anyway. Thinking about it now, we could probably combine both llyndnarz's idea and KungPao's idea. However, instead of manipulating water, he would transform H20 molecules into C2H6O(thanks Wikipedia!) molecules or ethanol. All water in the immediate vicinity would be transformed, including the water found in the human body. It would quickly screw up the body, quickly dehydrating it among other things and making it flammable.