It’s a level we all know, some of us by heart: the 1-1 level of Super Mario Bros. — arguably the first, perfectly executed in-game-tutorial-you-didn’t-know-was-a-tutorial. The level is precious. Sacred, even.

Until now.

A monster with Mario Maker 2 turned the first level many of us had ever played into a fiery hellscape from which, as of Tuesday afternoon, only five people have emerged unscathed. And one of them is YTSunny — the designer of the course.

It is by far the most anxiety I’ve ever experienced watching a video-game clip.

Mario Maker gives the player free rein to design any kind of Mario level they can dream up. It provides all of the blocks, goombas and pipes a true Marioficionado could ask for, plus all of the other design assets Nintendo itself has used across the Super Mario universe of games. This is the second iteration of the “Maker” series, which launched on June 28 for Nintendo Switch.

Once a designer is finished, he or she can launch the level and share a code for others to play. In this case, the designer was the first to clear the level. Four more finished after that.

YTSunny, a Mario pro, has nearly 600,000 subscribers on YouTube. One recent video, a walk-through of the first half-hour of Super Mario Odyssey, has 5 million views. YTSunny specializes in tutorials and Mario Maker levels, the latter of which have thousands of views a pop. On Twitter, the video of YTSunny’s own run had around 60,000 retweets as of Tuesday evening — and a lot of incredulous replies.

In this panic-inducing level, YTSunny seems to have thrown rotating fire bars everywhere. Except they are strategically placed; you can make it through the level in the 50 seconds allowed (Yes, of course there’s also a timer. Why wouldn’t there be?) if you follow the only route that will lead to success. And manage to not get hit by a wall of fire in the meantime.

If you want to try it yourself, YTSunny shared the code: YXL-D4C-TQF is what will get you access to the 1-1 from hell.

Just don’t expect to get that secret 1-Up.

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