Super Mario Maker isn't just a tool to create your own levels in the Mario universe, as it's also proven to be an instrument of hell - evil stages have been born inside this game, meticulously created by evil minds. One of these guys is Failstream, responsible for the trilogy of levels called the Flotilla Series.
But now this level has been cleared not only by Failstream but also by another brave hero called Flipsides, and if you think what you've played is hard, then wait till you see these levels get cleared, as there's so much to do in each one. Congratulations for besting the levels, though, and perhaps we may see even harder levels come in the future.