Applying a Patch
Contributors: Bivurnum
In order to play a ROM hack, you'll have to obtain that hack's patch.
Warning
I do not advise downloading pre-patched ROMs. They are likely outdated versions or otherwise not the ROM hack you want to play. Just patch yourself a new ROM with the creator's official patch.
The best place to find the most up to date version of a particular patch is on the original creator's official post. The PokéRom Codex (by themanynamed) is an ever-expanding database of ROM hacks that provides links to the appropriate places to find the patch wherever possible.
If the download is a .zip file, you will have to extract the patch (and any other files) from it. A lot of computers come with this capability already. Just right click on the .zip file and select "Extract All...". If you are unable do this, you may need to download an application that can do it. 7zip and WinRAR are two examples of such applications.
GBA patches will almost always be one of the following file types:
- .ips
- .bps
- .ups
- .aps
- .ppf
- .rup
Once you've downloaded a patch, you will need to apply it to an unedited ROM of the game it was based on. For example, if the ROM hack is a hack of Pokémon FireRed, you will need to apply the patch to an unedited copy of a FireRed ROM. The creator will usually tell you which version of the base rom you should use, but if they don't, I advise that you use one of these specific base ROM versions:
- 1986 - Pokemon Emerald (U)(TrashMan)
- 1636 - Pokemon Fire Red (U)(Squirrels)
Note
I cannot tell you where to find or download base ROMs. However, they shouldn't be hard for you to find if you look. Search engines are a wonderous thing.
Some hacks will provide you with a link that automatically patches the game for you. Others will provide a patcher application with the patch download (Unbound does this). Most hacks do neither. If you only have a patch, you will need to find a patcher to use. I'll tell you how to use my favorite online patcher, Rom Patcher JS:
Where it says "ROM File", you will provide the unedited base ROM you want to apply the patch to.
Where it says "Patch File", you will provide the patch for the ROM hack you want to play.
Once these are both filled in, just click the "Apply Patch" button and it will prompt you to name the new ROM and designate where on your device you would like to download it.
That's it! Now you can play the new ROM in the emulator of your choosing.