View source for How to patch a ROM

== Video ==
{{#ev:youtube|sKHVFJNj8c8}}

== Text ==

=== What you'll need ===
* A rom of Luigi's Mansion with the following properties:
** The file must be a .ISO file.
** It must be untrimmed. The file size should be around 1.4GB. If it's any lower, then you have a trimmed ROM and must acquire an untrimmed ROM.
** It must not have had any prior modifications done to it.
** It must be NTSC-U / US region, unless otherwise specified by the mod's author.
* The .xdelta patch file for the mod you'd like to play.

=== Instructions ===
1. After you've acquired the files above, navigate to [https://kotcrab.github.io/xdelta-wasm/ this link].

2. It should pull up a page that has two fields; Source file and patch file.
3. Click on the "Select file" prompt underneath "Source file" and select your Luigi's Mansion ISO.

4. Click on the "Select file" prompt underneath "Patch file" and select your .xdelta file.

5. Click "Apply Patch".

* If you receive an error such as "target window checksum mismatch (code -17712)", that means the ROM you added does not meet all of the specifications mentioned above. Make sure your ROM meets all of the requirements listed in the "What you'll need" section.

* If the patching was successful, it will prompt you to save the file. Save it wherever you'd like.