Since everyone seems to be dead with making any form of executable or .bat file to handle voice swapping, I'll just leave this here. My friend wants it so I might else well share it with everyone else anyways.
I would highly recommend you read this carefully before willy-nilly tossing things into your Grand Chase folder. I'm not going to make an executable or a installer of sorts because I figure you people should know what you're more or less doing if you're willing to replace your English voice files. If you already know how this works, then you should be able to handle it without reading this entire post but if you don't then do read this entire chunk of text.
More or less all the files you need are here : Korean Voice stuff
Backing up your English files is not necessary but will allow you to patch the game for any future updates without having to let the patcher download all the English voice files all over again. Simply copy the files you'll be replacing into a new folder or renaming them. Personally, I prefer just copying them over to a separate folder because it makes placing them back easier. Refer to the bottom of this post for a list of files that you should create a backup of.
KoreanResSet archives go into your ResSet folder.
The ResSet folder has to be split into two because of Mediafire's new rule regarding split archives (7z.001, 7z.002, etc).
KoreanSound archives go into your Sound folder
Create a shortcut of main.exe that is located in your Grand Chase folder and add __kogstudios_original_service__ to the end of the target line and it should look something like this.
"C:\SG Interactive\Grand Chase\main.exe" __kogstudios_original_service__
You need to run the game with this shortcut instead of the regular patcher or the patcher will simply replace the voice files which basically makes all that you've done with replacing the sound files completely pointless.
Whenever there is a patch released, just simply replace everything back with the English voice files (which you should have made a backup of) and run the patcher. You can copy over the Korean voices back once your game is done patching but do remember to run the game with the shortcut to skip the patcher.
If there's any reason for me to, I'll probably update the mediafire folder if I remember to or you can simply get the files directly from the Korean patch server at
This is simply a compilation of information from people who have done a voice patch so if you're going to give me any credit, it's either for compiling this or uploading the files to Mediafire. I don't claim any credit for the links or the shortcut executable to skip the patcher.
ResSet files : 27
Sound files : 12
If you encounter any missing voices, do let me know and I'll try to see if I'm missing out something.