Here's a virtuoso piano performance of the Super Mario Bros. theme - using one hand. If I'd remembered anything from my piano lessons beyond playing Old MacDonald on the black keys, I could probably describe how difficult this is.
A commenter asks "Was that one hand for left AND right hand, or was it just a really intense right hand part?" and the artist, RigorMortis999 replies, "the former becoming the latter."
Good thing Mario didn't run down to his final 100 seconds at the end.
[YouTube User RigorMortis999, thanks Isiah O.!]


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