I made a TAS I think it looks "very lightning 4-2", I am wondering if it is. Also it looks to be rta viable if tweaked a bit (it also has some wiggle room(i think)).

The file: https://www.mediafire.com/file/xr9oilxduruufa1/Super_Mario_Bros._%2528Practice%2529_lightning_4-2.fm3/file

practice rom used. (I wont be able to respond for the week this post is made because of a trip)

So I was playing around in smb1 and the hex editor tool(on fceux)and I found some memory values that will if done correctly SoftLock you like 20seconds before the wr. helpful stuff file download: https://drive.google.com/drive/folders/1EaWCASuI6o08koxz131AXD5A5qhsQhva , or https://github.com/UncleEnk/smb1-softlock-finding. How to do it: be lucky with the right memory values the die to the right goomba at the right spot. (may not be humanly possible I haven't looked far into it )