Back in the 2016-2019 (I couldn't remember exactly when), I saw a video on a video hosting website I don't remember the name of but it might have been in Japanese or has Japanese origins and has a default dark mode so it was not YouTube but I don't remember exactly what the video was about (possibly about remaking Super Mario Bros., no voiceovers or anything fancier) but all I know is that it was something about SMB1. I can't remember how the video started but it could have been a gameplay of the actual SMB1, but what I do remember is seeing the progress like making Mario able to run over 1 block wide holes like this: And there was more like I think making the enemies work or making Mario move but the end was showing the finished product, it was very close to the actual World 1-1 but the sound effects and music is completely different but I can't remember how they sounded like or if it sounded 8 bit (probably not) and I don't know from which game the audio came from.