(Solved) A strange Mario Bros hack. How is it working?

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Cyneprepou4uk
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(Solved) A strange Mario Bros hack. How is it working?

Post by Cyneprepou4uk »

The patch was made based on a ZIP file containing a modified ROM, instead of a modified NES file.

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I've encountered a Mario Bros hack called "New New New New Mario Bros" https://www.romhacking.net/hacks/1840/

Original ROM has 16k PRG and 8k CHR. Hacked ROM (according to the header) is 32k PRG and 8k CHR. However, file size is still 25k after patching.

When you look inside it, it's neither iNES nor UNIF, it's PK!

Image

Then comes some hack name info, and after that... IDK, I can't seem to find anything from Hex Editor in FCEUX at all, like interrupt vectors for example. Maybe data is compressed inside a file or something. Strange thing for me is that emulators can run this hack no problem.

This is the first time I've seen something like this. Can someone explain WTF is that about?
Last edited by Cyneprepou4uk on Wed Mar 15, 2023 7:32 am, edited 2 times in total.
Joe
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Re: A strange Mario Bros hack. How is it working?

Post by Joe »

Someone messed up when creating the IPS and accidentally created an IPS that will turn any file into a ZIP file containing the ROM.

Most emulators support loading ROMs from ZIP files, so it still plays.
Joe
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Re: A strange Mario Bros hack. How is it working?

Post by Joe »

Oh yeah, I forgot to mention: this means the IPS contains a full copy of the ROM, which is almost certainly against the rules at romhacking dot net. If you have an account there, you should report it.
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Cyneprepou4uk
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Re: A strange Mario Bros hack. How is it working?

Post by Cyneprepou4uk »

Yes, it's really a ZIP file. Thanks for the tip.
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jeffythedragonslayer
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Re: A strange Mario Bros hack. How is it working?

Post by jeffythedragonslayer »

Joe wrote: Tue Mar 14, 2023 10:38 pmromhacking dot net.
A good way to avoid two periods only three characters apart, and a challenge to pentest a C# game. :lol:
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TakuikaNinja
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Re: (Solved) A strange Mario Bros hack. How is it working?

Post by TakuikaNinja »

Welp, I was going to make an unofficial correction for that hack but I managed to find a bug with Mesen2's ROM/IPS saving...
It should be resolved soon, lol.
BTW, the original game suffers from a reset bug caused by the random power-up state of $2002. I've made a patch to fix that: https://www.romhacking.net/hacks/7648/
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TakuikaNinja
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Re: (Solved) A strange Mario Bros hack. How is it working?

Post by TakuikaNinja »

As of this post, the hack has been corrected by yours truly to produce a ROM file instead of an archive file.
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