Hi everyone, I'd like to ask a question about something.
Well, I'm playing MH3U on Cemu on my PC, and I recently bought a second-hand 2DS.
In my Cemu save, I'm right at the end of the Moga Village quests. And I really want to transfer my Cemu save to the 2DS.
Because I don't want to farm Brachydios set (It took me 2 days to get the gem drop) and have to redo all the Moga Village requests.
And I'd like to use the 2DS to play because if I use the homebrew ''artic base'', I can connect my 2DS to Citra and use the Citra servers to play MH3U online via LAN.
and searching on google I found ( https://github.com/fadillzzz/3usavetools ) that promises to convert saves from cemu to 3ds or 3ds to cemu.
and I have a lot of doubts about whether this is really safe, because it's not even an app, it's a python code. and I would like a second opinion from someone who really understands these things and can tell me if it's safe or not.
I appreciate your help if possible
MH3U save data Transfer (cemu -> 3ds)
Re: MH3U save data Transfer (cemu -> 3ds)
Being hosted on github and completely open-source (the code that runs is publicly visible to all and anything malicious would have to be really hidden to evade the public eye), there is near to no threat of this being malicious to your computer. Since it's not really an executable, and it's not running any scripts with elevated permissions, I'd say there's no real threat of it being malicious either. The scripts are also fairly short and running mostly mathematical operations and shifting bits around, so there is really not enough code to hide a virus in it or anything like that. The worst thing it could do is not work as a save converter and mangle your original save, so do keep a backup of that before trying to run the script on it.
As for the 3DS side, I imagine you'll need some kind of homebrew like Checkpoint to be able to import and use the save data, since I imagine it will spit out a 3DS emulator compatible file. This obviously implies that you've gone through the process of jailbreaking your 2DS to be able to execute custom code. I might be wrong, though - briefly looking over the code, I didn't see the exact file format in question.
From what I know, there was an official 3DS to WiiU application for the 3DS called "The Monster Hunter 3 Ultimate Data Transfer Program". I don't know if it works backwards or has an equivalent on WiiU hardware to go back, but you could always give it a look.
As for the 3DS side, I imagine you'll need some kind of homebrew like Checkpoint to be able to import and use the save data, since I imagine it will spit out a 3DS emulator compatible file. This obviously implies that you've gone through the process of jailbreaking your 2DS to be able to execute custom code. I might be wrong, though - briefly looking over the code, I didn't see the exact file format in question.
From what I know, there was an official 3DS to WiiU application for the 3DS called "The Monster Hunter 3 Ultimate Data Transfer Program". I don't know if it works backwards or has an equivalent on WiiU hardware to go back, but you could always give it a look.
— Arty
I'm just a voice, pal.
Host of ARTV. Poseur anarcho-punk. Occasional writer, programmer and editor. 4級 in Riichi Mahjong.
MH1-HR20 · MHG-HR13 · MH2-N/A · MHP3-HR6 · MH4U-HR5 · MHXX-N/A · MHR/SB-MR503:HR757
I'm just a voice, pal.
Host of ARTV. Poseur anarcho-punk. Occasional writer, programmer and editor. 4級 in Riichi Mahjong.
MH1-HR20 · MHG-HR13 · MH2-N/A · MHP3-HR6 · MH4U-HR5 · MHXX-N/A · MHR/SB-MR503:HR757
-
mossguardian
- Greenhorn
- Posts: 1
- Joined: Mon May 12, 2025 11:44 pm
Re: MH3U save data Transfer (cemu -> 3ds)
some background for me (optional read): I finally modded my 3DS I've had for about the last 15 years about a month or two ago. I started with MHWorld back in 2019 or so, and had some success in MHGenU on my switch, so i decided to give 3U a try on my 3DS (4U will come after, I was more interested in the water combat. Also, gen3 is when we first saw something resembling the modern HH, and I love to doot). I got to Qurupeco with minor difficulties, and a lot of fun. But, I found out that MH3U (on 3DS) doesn't support online play without a Wii U, and I don't have one of those (or the money to hunt for one). Thus began the quest of getting a copy of MH3U running on Cemu, because what is monster hunter w/o friends?
TLDR; here's a tutorial for how to transfer the MH3U save data from 3DS to Cemu, and vice versa. This does assume you have a modded 3DS, and that you have both the MH3U save transfer tools listed above AND a version of python downloaded. I'll explain how to use it but you need python to run the transfer tool (there is also another download but its automatic w/ the transfer tool and i'll explain there)
A disclaimer that I haven't run the process from Cemu to 3DS, but it should still work fine. There are specific instruction for the Cemu>3DS pipeline.
0) disclaimers
0a) Whether you're transferring from Cemu to 3DS, or vice versa, make sure to save an extra copy of the original save data in case something goes wrong.
0b) I'll specify if the step is only for one process or the other. If it doesn't say "for 3DS" or "for Cemu", make sure you don't skip it.
0c) I am not a professional, so seriously, please take steps to ensure you don't lose a big save that meant a lot to you. Part of the reason i puzzled this out is because I didn't want to save edit to get all my progress back from 3DS
1) locating your save data
1a) For 3DS, this involves using Checkpoint to make a backup copy of the save data, which will be located at "D:\3ds\Checkpoint\saves\0x00AE4 MH3U\[save-data-name]" ("D:" is the root of your 3DS' SD card). The name of the save defaults to the time and date you made it, but you can also change the name of the file before creating it and shouldn't matter for this process. You'll open that folder and find the "user#" file. It won't have a file type, and that's ok.
WARNING: If you don't do this, the save file will be too big for the save translator to handle, and an error will occur. It won't corrupt the file, but it will be annoying.
1b) For Cemu, you'll open Cemu and go to the top-left, selecting "File". Hit "Open Cemu Folder" (this is just the simplest way for me to get here). Now you'll click on your "mcl01" folder (that's just what the Cemu setup tutorial told me to call it) and navigate as follows; usr/save/00050000/10117200/user/80000001. Once you open the last folder, you'll see about a dozen files, but the only one(s) that matter are at the bottom; the "user#" files. It won't have a file type, and that's ok.
2) transferring your save
The save data conversion tool can be run with commands with just Python. The tool's documentation provides the structure of the command, but if you're not confident in using commands or want to follow this guide to a T, then you will also need to install PyQt5. This is a Python package that allows for the creation and use of GUI (an interactable window). The conversion tool has a more user-friendly GUI version created with PyQt5 which does the exact same thing as running it using the command line. It's what I used.
2a) When you download the tool, just extract the folder, open it, and click on the next folder [there should only be one]. The address should be "C:\Users\[USER]\Downloads\3usavetools-main\3usavetools-main", assuming you kept it in the downloads folder.
2b) Right-click the blank space, and hit the prompt "Open in Terminal". This will open a python "powershell", and you need to do two things. First, type "pip install pyqt5". This will install PyQt5, which will allow the tool to launch properly (and frankly, idk how to do this without it). Second, type "python app.py", exactly like that. Without the quotations. This will open the app, where you can convert your save data.
2c) Select "Load save file", and navigate to your 3DS/Cemu save data. You can also copy the path and paste that in the box to the right of it. In the second box, you are effectively doing the same thing as clicking "save as..." on a google image. Click "Set output file", and navigate to where you want the file to end up. Then, give the file a name, and hit "Convert". Alternatively, you can copy and paste the file paths, though you'll still need a name for the new file.
3) putting your new save into the game
3a) If you started on 3DS, and now have a Cemu save, navigate to your Cemu "mcl01/usr/save/00050000/10117200/user/80000001" folder, wherever you keep it. Paste your save in under the name "user1", "user2", or "user3". The number should correspond with the placement of the slot in-game, from top (1) to bottom (3). Happy hunting!
3b) If you started on Cemu, and now have a 3DS save, navigate to your 3DS SD card's "D:\3ds\Checkpoint\saves\0x00AE4 MH3U" folder. Make a new folder, as this will be what shows up as a backup save in Checkpoint. Put your new save in the new folder under the name "user1", "user2", or "user3". The number should correspond with the placement of the slot in-game, from top (1) to bottom (3). Happy hunting!
TLDR; here's a tutorial for how to transfer the MH3U save data from 3DS to Cemu, and vice versa. This does assume you have a modded 3DS, and that you have both the MH3U save transfer tools listed above AND a version of python downloaded. I'll explain how to use it but you need python to run the transfer tool (there is also another download but its automatic w/ the transfer tool and i'll explain there)
A disclaimer that I haven't run the process from Cemu to 3DS, but it should still work fine. There are specific instruction for the Cemu>3DS pipeline.
0) disclaimers
0a) Whether you're transferring from Cemu to 3DS, or vice versa, make sure to save an extra copy of the original save data in case something goes wrong.
0b) I'll specify if the step is only for one process or the other. If it doesn't say "for 3DS" or "for Cemu", make sure you don't skip it.
0c) I am not a professional, so seriously, please take steps to ensure you don't lose a big save that meant a lot to you. Part of the reason i puzzled this out is because I didn't want to save edit to get all my progress back from 3DS
1) locating your save data
1a) For 3DS, this involves using Checkpoint to make a backup copy of the save data, which will be located at "D:\3ds\Checkpoint\saves\0x00AE4 MH3U\[save-data-name]" ("D:" is the root of your 3DS' SD card). The name of the save defaults to the time and date you made it, but you can also change the name of the file before creating it and shouldn't matter for this process. You'll open that folder and find the "user#" file. It won't have a file type, and that's ok.
WARNING: If you don't do this, the save file will be too big for the save translator to handle, and an error will occur. It won't corrupt the file, but it will be annoying.
1b) For Cemu, you'll open Cemu and go to the top-left, selecting "File". Hit "Open Cemu Folder" (this is just the simplest way for me to get here). Now you'll click on your "mcl01" folder (that's just what the Cemu setup tutorial told me to call it) and navigate as follows; usr/save/00050000/10117200/user/80000001. Once you open the last folder, you'll see about a dozen files, but the only one(s) that matter are at the bottom; the "user#" files. It won't have a file type, and that's ok.
2) transferring your save
The save data conversion tool can be run with commands with just Python. The tool's documentation provides the structure of the command, but if you're not confident in using commands or want to follow this guide to a T, then you will also need to install PyQt5. This is a Python package that allows for the creation and use of GUI (an interactable window). The conversion tool has a more user-friendly GUI version created with PyQt5 which does the exact same thing as running it using the command line. It's what I used.
2a) When you download the tool, just extract the folder, open it, and click on the next folder [there should only be one]. The address should be "C:\Users\[USER]\Downloads\3usavetools-main\3usavetools-main", assuming you kept it in the downloads folder.
2b) Right-click the blank space, and hit the prompt "Open in Terminal". This will open a python "powershell", and you need to do two things. First, type "pip install pyqt5". This will install PyQt5, which will allow the tool to launch properly (and frankly, idk how to do this without it). Second, type "python app.py", exactly like that. Without the quotations. This will open the app, where you can convert your save data.
2c) Select "Load save file", and navigate to your 3DS/Cemu save data. You can also copy the path and paste that in the box to the right of it. In the second box, you are effectively doing the same thing as clicking "save as..." on a google image. Click "Set output file", and navigate to where you want the file to end up. Then, give the file a name, and hit "Convert". Alternatively, you can copy and paste the file paths, though you'll still need a name for the new file.
3) putting your new save into the game
3a) If you started on 3DS, and now have a Cemu save, navigate to your Cemu "mcl01/usr/save/00050000/10117200/user/80000001" folder, wherever you keep it. Paste your save in under the name "user1", "user2", or "user3". The number should correspond with the placement of the slot in-game, from top (1) to bottom (3). Happy hunting!
3b) If you started on Cemu, and now have a 3DS save, navigate to your 3DS SD card's "D:\3ds\Checkpoint\saves\0x00AE4 MH3U" folder. Make a new folder, as this will be what shows up as a backup save in Checkpoint. Put your new save in the new folder under the name "user1", "user2", or "user3". The number should correspond with the placement of the slot in-game, from top (1) to bottom (3). Happy hunting!