YouTube channel Boomstick Gaming has recreated the excellent vertical platforming roguelike rather accurately within Nintendo's Mario-themed course creator. Just like the real game, the objective is to make it to the bottom, while attempting to get the highest score possible. This version even has a built-in easy setting – allowing you to have a practice run.
If you would like to try out this course for yourself, the code is 2KH-BN0-7VG. Be sure to check out the Nintendo Life Super Mario Maker 2 Course Search as well. And if you're interested in playing Downwell, you can purchase it from the Switch eShop for $2.99 / £2.69.