Undertale on RG351P & RG351M

Last updated: 22MAR2021 (see Changelog for details)

Today we’re going to install and play Undertale on the RG351P and RG351M thanks to the AnberPorts app. Installing this game is a little tricky, because it uses assets from the Linux version of Undertale. In this guide I’ll show you how to extract those Linux files using a Windows PC.

Note that AnberPorts now works on both ArkOS and 351ELEC starting today, but the 351ELEC version is still buggy (for example, Undertale won’t launch yet).

Purchase and download Undertale

In order to run Undertale on your favorite retro device, you need to have the retail game assets. I recommend purchasing the game from GOG.com, where you can easily grab the Linux installer file, which has the exact assets you need. You cannot extract the correct assets from the PC or Mac versions of the game, you need the Linux version.

Once you have purchased the game, it will show up in your library. Go into the Games section on your profile, and click the arrow at the bottom-right of your Undertale game, and select “View Downloads”. Change the system to Linux, and then click on the link under “Download Game Installers”. It will be a 128MB file in .sh format. Save that onto your PC.

Install AnberPorts and prep the Undertale port

If you don’t have AnberPorts already, go to this page and download the zip file. You can’t miss it, it’s a big ‘ole button. Unzip this file, and inside you’ll find an AnberPorts folder and an anberports.sh file.

Put your RG351P or RG351M microSD card into your PC. On the EASYROMS (ArkOS) or GAMES (351ELEC) partition of your device’s SD card, find the “ports” folder, and place these two AnberPorts files in there. Place the SD card back into your device, and power it on.

Navigate to the Ports section, then launch AnberPorts. While connected to WiFi, select the “Update” option and go through the prompts. It’ll kick you out of AnberPorts, go back into it, and then go to the “Games” section. There you will see a list of all sorts of ports you can install. If you’re interested in installing any of these other ports, check out this page from the AnberPorts wiki page which will show you the exact retail files you need in order to run each game.

Head to the Undertale section, and then press “A” to download and install the game launcher. You’ll need to be connected to WiFi for this step, too. Now that we have a means to run the game, we need to add the Undertale game assets. Here is where it gets tricky (and a little exciting, too).

Install Debian for Windows 10

On your PC, go to the Microsoft Store, and then search for “Debian“. Install this free app, and then try and launch it. It will tell you that you need a Windows Subsystem for Linux (WSL). Head to this page, and in the “Manual Installation Steps” section, you’ll see the following code:

dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart

Go ahead and copy this code. Next, in your Windows Start Menu, search for the word “Powershell” and when the app pops up, right-click on it and select “Run as Administrator” and confirm the prompts. Inside PowerShell, paste that code above, and hit Enter. Once that is done, close out your windows and restart your PC.

Once you’ve rebooted, start up Debian again, and this time it will launch and install. It will prompt you to create a username and password.

Extract the Undertale assets

Open up the folder where you installed the Linux version of Undertale (the 128mb .sh file), and keep that window open and handy. Open up Debian and type the following:


Next, grab that .sh file and drag it into the Debian window. It will populate the rest of the code with the location of the .sh file, but you need to make some alterations to it. Change all of the backslashes to forward slashes, and remove the “C:/” from the code. Your final code will look something like this (assuming you put the .sh file in a folder named “undertale” on your Desktop):


Hit Enter and you’ll be greeted by the user license. You will need to confirm “Y” that you want to see 21 more lines, just keep hitting Y and Enter until you’re at the bottom, when it asks you to accept the license. Next it will ask you to confirm the destination. Just press “1” and Enter. It will then ask you to create shortcuts, press “1” and Enter and then “2” and Enter to deselect these. Finally, press Enter to finish the install.

Now you need to find the installed files so you can grab those assets. Note that you will need to enable hidden files in order to find the “AppData” folder. Here is the file path of your assets:

This PC / Local Disk / Users / (username) / AppData / Local / Packages / TheDebianProject… / LocalState / rootfs / home / user / GOG Games / Undertale / game

Inside that folder you will find an “assets” folder and a “runner” file. Copy these files over to the ports/Undertale folder on your device’s SD card (within the EASYROMS or GAMES partition).


You, my friend, have now installed Undertale onto your device. All you have to do is put the SD card back into your device, navigate to the Ports section, and launch Undertale. Here are some keys:

SELECT = exit game
(hold) START = exit game (but doesn't really work)


I’ve been told that if you purchase Undertale directly from its website via the Humble Store, it comes with a Linux version that is already extracted (meaning that you can skip the Debian/extract steps above), but I haven’t personally tested this.

It is also possible to use the Windows version of Undertale on your RG351 device, but results will vary based on the game version you have installed. I haven’t tested this myself. This assumes that you have already installed AM2R via AnberPorts on your device. Here are the steps

  • copy runner from /roms/ports/am2r folder over to /roms/ports/undertale folder
  • create /roms/ports/undertale/assets subfolder and put all .ogg files in there
  • rename mus_bgflameA.ogg to mus_bgflamea.ogg for case sensitivity
  • and finally rename data.win to game.unx


– published guide
– added notes about Humble Store and Windows extract based on feedback

4 thoughts on “Undertale on RG351P & RG351M

  1. Wow! I have the Steam version, but I also use Linux for gaming so I assume I would be able to extract the assets via my installed Linux version. I’ll try later, thanks for the guide! By the way if anyone wants to try running Linux on your computer, it’s not that scary πŸ™‚ and you can still keep Windows around for a few things if needed.


  2. You might be able to extract the assets without going through WSL, specifically rename the .sh file to .gz and open it in 7-Zip, the assets should be under \data\noarch\game\, I don’t own the game on GOG so I can’t double check this.

    For Steam you can open the console via Win+R, type the following: steam://open/console
    A console tab should show up in the Steam client, where you can enter the command: download_depot 391540 391544
    Expect the following output:
    Downloading depot 391544 (119 MB) ..
    Depot download complete : “C:\Program Files (x86)\Steam\steamapps\content\app_391540\depot_391544” (227 files, manifest 5730345506996883260)

    the assets can be found in the folder Steam supplied, which might be on a different drive depending on your settings


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