See, Super Mario Maker is a game about making and sharing Mario levels with the community. Some are hard, some are stupid, some are silly and some (most) are simply bad.
Nintendo had to make sure that these levels could actually be, you know, cleared, so they put a rule in place. You can’t upload a level until you’ve beaten it. Moor’s been working on beating “Trials of Death†since January of 2016.
He streams his attempts, and he’s even put out trailers. You should hit the source link below for Waypoint’s brief chat, it’s a good one.
Article source: https://www.technobuffalo.com/2017/07/22/super-mario-maker-level-maker-cant-beat-it/