Super Mario Maker 2 is essentially a canvas for making whatever kind of Mario level you want, be it crane games and puzzle levels, or even a narrative journey. PangaeaPanga, a popular Mario Maker creator, has used it to create a devilish twist on one of the hardest archetypes of custom Mario courses around.
Certain custom Mario courses are known for their sheer difficulty and use of precision movement you wouldn't find in an average, Nintendo-made game. They're referred to as Kaizo levels, named after the Kaizo Mario World ROM hack. (There's sometimes a further distinction between Panga's level creation style and other Kaizo levels, but we don't need to get into that here.)
Using a mix of Super Mario Maker 2's new mechanics, like turning the world upside-down underground when Night Mode is active, he's made a course called Pit of PePanga: Panger Things. (Like Stranger Things, and the upside-down.) He tweeted out video of himself clearing it during a stream, and it looks ridiculous.
I won't try to stop you from attempting this, but just keep in mind, while left and right still work the same, up and down are different, making all these lateral vine jumps a lot scarier than they already are. I think I'll safely watch from a distance.
If you want to check out some other courses that might be set at a (mostly) lower skill threshold, check out some of our early favorites from the Course World. Oh, and read up on all the story mode secrets, so you can grab Night Mode for yourself and make your own evil upside-down course.