I agree with the fact that Munch and Abe have powers which dont relate to their names, so I dont think that Squeek will have a power to do with 'squeeking', although, the idea of possessing soundwaves sounds interesting, its possible, but highly dubious.
Maybe he has to power to 'convert' enemies, meaning that he can make them follow him around like a Mudokon, instead of possessing them, but I also doubt that
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