Modding MKDD

Modding MKDD

Yes. You can do it. You can customize the tracks, move items, make the computer players throw themselves in the water remove the ennemies that bother you, even better, put them in the lava.Internet’s imagination will be the limit to the mods we will be offered.

Why Mario Kart Double Dash ? Wii has mods already, loads of tracks… But I do not like the game engine on Wii. I prefer the nervous style of MKDD. That’s it, that is the only reason :) A dream would be to port the tracks of Mario Kart Arcade Grand Prix (the game engine sucks even more) on Double Dash. But I do not know enough about the track formats to know how hard it would be.

End of introductory bullshit.

Basically, Gamecube games are like these old PC Games : if you wanted to see the last animation of a game, or the alternate endings, you could (back in the days) navigate throught the files on the CD. I am thinking about Myst, because this is how I spoiled myself.

But, it is slightly harder when it comes to Gamecube Games. Why ? (don’t do that - I did this already) If you try to insert a Gamecube game in your disc drive, nothing will happen. It may also freeze your computer. And I decline every responsibility in case something happens to you or your computer :)

So, the first step to obtain the contents of a disc is to rip it. You can do it from a Wii, with the right channel… But I will assume that you have a clean .iso file of Mario Kart Double Dash.

What’s next ? Now we want to look in this ISO. For this, the best tool is GC rebuilder. It allows you to navigate through the files of the game, like any explorer. (I will link the relevant pages to get these tool at the bottom of the page, no need to rush, you have to understand every step if you want to produce something decent).

So far, everything looks quite easy. What is so difficult ? Well. Opening the files with the correct editor is the hard part. But with Gamecube games, the format are not common. Besides, files are often compressed. And Nintendo did not use the most usual compression algorithms, so you need specific decompression tools. And then, when you have uncompressed the files, you still have to edit them. On old computer games, some movies of the game could be in Quicktime format / avi… But it is not that easy !

Assuming you modified the files (per example, the position of the ennemies on a track), you have to recompress them (ArcPack allows you to do this), and recompress the whole ISO, and at last, play (Dolphin, the emulator, is a good way to try quickly your modifications).

No Step Tool
1 Extracting files from the iso GCREeX (GCIT or GC Rebuilder may work as well)
2 Decompress the tracks ArcExtract
3 Edit the tracks douBOL
4 Recompress the tracks ArcPack
5 Rebuild the ISO GCREeX (or GCIT or GC Rebuilder)
6 Play Dolphin or your console

Congratulations for making it this far! Below are the tools and a short explanation of what they do. In some cases, they are game specific. They are at the bottom of the table.

Tool Address Purpose
Dolphin Run a Gamecube image on a computer (testing purpose)
GCREeX ISO decompression and recompression
ArcExtract Decompression tool
ArcPack Compression tool
douBOL MKDD : editing the course files

That’s it, you do not need anything else! So with these in hands, let’s continue step by step.


Step 1 - extracting and decompressing the track.

Put the ISO and gcreex in the same folder and enter the following command (either using the command line). If you do not know how to do that, but work in a Windows environment, just create a text file, put the following in it, rename it “extract.bat”, and double click on the bat file.

gcreex -x mkdd.iso

On modern machines, this should take less than 10 seconds. Now you should have a folder (GSM04 I think) containing all the data, that you can now explore.

Step 2 - extracting the track

Once you found the track you are looking for, copy it. Drag it and drop in on “ArcExtract.exe” (or, in the console, type “ArcExtract mytrack.arc”). Now you should have a directory, named after your track containing files wiht BMO, BOL… extensions. Now open douBOL, and select the BOL file. You should have a screen like this.

Step 3 - edit the track

Now you can perform the modifications you want. Everything that is listed in the program can be changed. Don’t forget to save your files :)

DouBOL Capture

Pro tip: The coordinate system is not really intuitive. However, the fact that nearby items on the map are usually close to each other on the item list allows to guess more easily what are left and right, large and small, in terms of X,Y,Z.

Pro tip 2: You can go beyond the use of the GUI of douBOL, and use the source for more tedious operations ! If you want your opponents to go backwards, per example !

Step 4 - recompress the track

Once you are done editing the track files, just drop the folder on ArcPack, it will produce a new .arc file, which you have to put back in the game folder (replacing the previous .arc file)

Step 5 - recompress the ISO

Once the replacement of the arc files has been performed, you need to use gcreex once again.

gcreex -x folder_name [should be GSMO4]

This should take 10 seconds on modern computers. Do not worry if the created file is much lighter than the original ISO. The game is actually much smaller than the image.

Step 6 - play

Launch the file out.iso (which appeared in the same place as gcreex) with Dolphin, select the track you modded, and enjoy :)

Side note: If you modified one of Luigi Luigi2 arc file, note that they are selected depending on the power you choose (50cc, 100cc or 150cc). The Grand Prix in 50cc loads Luigi.arc, and 100cc (150cc) loads Luigi2.arc. These tracks differ by a small wall, separing the two roads (which are not separated usually)

What is next ?

So, you went this far without any idea of what to do ? Well, some fun modes could be a race in Luigi’s mansion (yes, you can import the tracks from the battle mode, but the modifications, building the checkpoints… Are up to you ! Or create a harder version of the game, with more (and faster) cars on the cities…

At last, thank you> for your help :)

Or simply play the game again ?


Passionate about Gamecube, coding, statistics, beta games...

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