Team 0% is attempting to clear every level in Super Mario Maker before the servers shut down on April 8. (New level uploads have been disabled since 2021, so there is no danger of new levels appearing at the last minute.) As of a few days ago, only a single level remains: Trimming the Herbs, uploaded in 2017 by Ahoyoo. (See also Ahoyoo’s original upload video.)
The level is short but extremely precise, requiring Mario to use Bob-ombs to precisely remove Piranha Plants and collect coins while navigating a tight space filled with spikes. There have been over 200,000 attempts so far! If you have a Wii U and feel like you might be a Mario master, this is your opportunity to pick up the final First Clear in Super Mario Maker history.
Sorry, yeah, it is intended that all levels are beatable. To upload a level you must prove that it is beatable by clearing it from the beginning without dying, and then clearing it again from each checkpoint (if there are any) to prove that it can also be cleared from any checkpoints.
Hacked levels have existed that cannot be cleared, but they can be reported and Nintendo takes them down. They should all be taken down by now, but in any case if it’s obviously impossible (the goal is completely blocked by impenetrable walls) Team 0% marks them as hacked on their spreadsheet in addition to reporting them, so they wouldn’t count.
In this game you can download levels and see the full level in the editor, so it isn’t possible to make a level that is “practically” unclearable using hidden information. Any things like hidden keys, “passcode” sections (where you need to hit blocks a certain number of times in order to manipulate things hidden off screen), etc. are trivially defeated by viewing the level in the editor.
I know I’ve seen “cryptographically secure” levels (as in, you can only possibly beat it within a human lifespan if you know the specific “combination” or “cryptographic key”), but maybe only in Super Mario Maker 2.
And I’m not sure if in 1 you can inspect the whole level. The SMM2 cryptographically secure ones I’ve seen rely on mechanisms that must remain off-screen the whole time or else it’s trivial to derive the key.
It’s only in SMM2, which doesn’t allow you to edit other people’s levels. And actually there is now a 3rd party tool to view SMM2 levels so those levels are now exposed as well.
Cool system; thanks for the run through!