though they can cut through almost anything there have been multiple occasions when something hard/dense enough repelled it without being of something equal or better. also worth noting is that even though it can cut through most things it doesn't mean that it won't meet any resistance in the process. though i'm sure he's climbed some things he definitely shouldn't have been able to, the usual 'climbing a wall' ain't one of them.
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The King Wang.
Listen up Urinal Cake. I already have something that tells me if I'm too drunk when I pee on it: My friends. - Colbert.