Hello everyone. I discovered the cause of the bug preventing the player from completing World 1-2, and was able to fix it. This allows the game to be beaten, since you can now go to 1-3 and finish the game. Now that I have made a version of the game that can be beaten, could this fixed version possibly be added as additional categories?

World 1-3 would make for an interesting level that would be tough to optimize in runs and would allow for individual frames to be saved, much like how individual frames can be saved in 1-2 in the standard version of Petscop !!. Not only could you make an "Any%" and an "Any% (Pipeless)" category for this new version, but you could also make an "All Levels" category using the Second Quest level select feature much like the "All Levels" speedrun of the hack "Super Mr. Krabs."

Here's a link to my fixed version of the game. Just use this patch on an unmodified ROM of Super Mario Bros. and you're good to go: https://drive.google.com/file/d/1p2XDBdL9t4G4Wy710PBel8QX7zta4dgs/view?usp=sharing

Nice find! I will add it now. I just played through it a bit and I saw that the piranha plants have also been added in the 1-2 level, which is a pretty nice addition. I will definitely add the categories, do you think I should add new categories or make the new patch a sub category in the existing Any% and Any% pipeless categories? I will also add the All Levels category, so for that category do you need to just beat the game and then do World 2-1 to 8-4 in second quest?

The Piranha Plants not spawning in 1-2 was actually a side effect of the bug that prevented 1-2 from being completed, so they spawned by fixing the bug. I think the new patch should be added as subcategories just to keep things simple.

Also, for All Levels, you can't just start in 2-1 and play until 8-4 because completing each world triggers the code to have you return to the title screen, since that code will always trigger if the world counter is equal to or greater than the "final world", which in this hack is World 1. This means that you have to manually select each world on the title screen, which makes things interesting because you can't keep your powerups in-between worlds. Basically you would select World 2, beat 2-5 and return to the title screen, select World 3, beat 3-4 and return to the title screen, etc. Whether soft resetting to return to the title screen quicker should be allowed or not is up to you.

Edit: By the way, I haven't exactly fixed 1-2 crashing. I was able to fix the enemy objects not spawning when you start the level, which was why the 1-2 above ground warp didn't load and the Piranha Plants didn't spawn, but I haven't quite figured out how to fix the game crashing when respawning at the midpoint. In fact, if you could access the 1-2 underground in this new version, it would still crash just like respawning at the midway point does. None of this really matters for speedrunning, but I guess 1-2 is just a weird level. ¯_(ツ)_/¯

Ah right! Sounds good, thank you for making this patch! I will add the new categories soon. I don't really know whether to allow soft resetting to go to the title screen quicker, I think ill probably disallow it for now as it seems more natural to go back to the title screen by just waiting, however if people want to allow soft resets then I don't mind allowing it.

Hey! I think I have finished adding all the new categories, I am not too used to adding new categories so please tell me if I missed anything! I added the link to the patch in the rules of the category that requires it, hopefully you are alright with that. Please just respond in this forum if you want me to change anything.