Steam Deck - Installing Deus Ex with Kentie's Launcher, GMDX, or other mods

A step-by-step guide on getting Deus Ex working perfectly on a Steam Deck with Kentie's Launcher (Deus Exe), as well as any other mods you want, such as GMDX, BioMod, The Nameless Mod, etc.

Introduction

Deus Ex is undoubtedly my favourite game of all time, and I was determined to get it up and running on the Steam Deck. However, it needs a specific fix (Kentie's Launcher, aka Deus Exe) to run at the Steam Deck's native resolution, as well as to do other things like customise the FOV, use a more modern renderer, etc. I designed a control scheme which I think works really well, and this is also covered in the guide.

Deus Ex also has some amazing mods, most of which add new gameplay content, so I wanted to get these running on the Steam Deck too. By following this guide, you'll get Deus Ex set up to run perfectly on the Steam Deck with whatever mods you want, with Kentie's Launcher working at the same time, and it will even track your gameplay time and allow use of community controller layouts on Steam as normal.

Also, if you find this guide useful, I wrote similar ones for Deus Ex: Invisible War and Vampire the Masquerade: Bloodlines.

Downloads

Only one download is mandatory for this: Kentie's Launcher[kentie.net]. I used version 8.1, which is the newest one as of right now. If you don't want any other mods (which is what I'd recommend for a first playthrough), download this and skip to the Kentie's Launcher section below.

Next, download whatever mods you want - the installation process is more or less the same for all of them, and I give specific information on installing the most popular ones at the end of the guide.

I've played this game a million times, and particularly enjoy the Give Me Deus Ex (GMDX) mod, so I will be using GMDX v9, which you can find here on ModDB.

Note: This guide originally covered the installation of GMDX v9 RSD, the successor to GMDX v9 made by a different team, but I encountered a game-breaking bug when I used this version (see the GMDX v9 RSD section at the bottom) so I changed the guide to show the original GMDX being installed instead.

Installing Mods

If you're only installing Kentie's Launcher, feel free to skip to the next section. I've tried to make the following as basic as possible, because I remember how confusing it was to use Linux for the first time ever when I got my Deck.

1.

IMPORTANT: Download the game and run it once, then quit from the main menu. If you don't do this, most mods won't install properly. Also, when you run the game, if your list of renderers is blank, delete whatever you've entered in the "Launch options" in properties.

2.

Switch to desktop mode. Navigate to wherever your downloaded files are - in my case, they are in the Downloads folder. Any .exe files can be left alone, but you should extract any .zip files by right-clicking them, then clicking Extract -> Extract archive here, autodetect subfolder.



Each archive will extract into its own folder.

3.

Add the .exe to Steam as a non-Steam game. To do this, open Steam, select Games -> Add a Non-Steam Game to My Library, click "browse" in the bottom-left corner, then browse to the .exe file for your mod and select it.


Once the mod is shown in the list with a tick, click "Add Selected Programs".

4.

Set the installer's compatibility to Proton 9.0-4. To do this, right-click it in your library list, open "Properties".



Then, click "Compatibility", tick the box, and select "Proton 9.0-4" from the drop-down list.

5.

Unfortunately, the default installation path for Steam games is inside a hidden folder, and the installer will not be able to see it. To fix this, we must create a shortcut in an easy location. Right-click Deus Ex in your library, then click Manage -> Browse Local Files.



This will open the installation folder - click the file path at the top, then highlight and copy the entire thing.


Now, navigate to a place the installer can see (I always use /home/deck/), right-click and select Create New -> Link to File or Directory.


Name it whatever you want - I name mine DeusEx here - then paste the file path into the lower box. When you press "OK", a shortcut to your Deus Ex folder will be created in the deck folder.

6.

You're good to go! Run the installer .exe from your Steam library and it should open up as normal. Once you reach the part where you give it the installation directory, click "Browse" and navigate to where you placed the shortcut in the previous step.



For me, the path looks like the below. Run the installer as normal, and do not launch it at the end if it offers to - we are not done setting up.

7.

Deus Ex relies on two files to know which mod is running, and we must tell it where they are.
In your Deus Ex installation folder, you should see a subfolder where the mod has installed (GMDXv9 in this case).



Open this subfolder, then go into the "System" folder.



In here you should see two .ini files - one will usually have the name of the mod, and the other will be called the same thing with "user" afterward.



In your steam library, right-click Deus Ex and select "Properties". In Launch options, we have to enter the below text. As you can see, the two file paths start from the Deus Ex folder and point to the mod subfolder, then the System folder, and then the two ini files - I have colour-coded this to hopefully make it clearer. Other mods will have a different folder and ini name, but the structure is more or less the same every time. The launch options for other popular mods are discussed at the bottom of the guide.

INI="..\GMDXv9\System\gmdx.ini" USERINI="..\GMDXv9\System\GMDXUser.ini"

8.

Your mod is installed! Now you just need to install Kentie's Launcher, which is much quicker than this, and you're good to go.

Kentie's Launcher (Deus Exe)

1.

Navigate to wherever you put the downloaded Kentie's Launcher. If you didn't already, right-click it and select Extract -> Extract archive here, autodetect subfolder.



This will create a new folder called DeusExe-v8.1. Inside this new folder, you should see two files, shown below.

2.

Open your Deus Ex installation folder (right click in your Steam library and Manage -> Browse Local Files), then navigate into the System folder. Copy and paste the two Deus Exe files into your Deus Ex installation folder, as shown below.

3.

On Windows, deusex.exe (the new file) would replace DeusEx.exe (the old file), but on Proton they can exist together. Take DeusEx.exe and rename it to something like DeusEx-old.exe, then rename deusex.exe to DeusEx.exe so that when Steam opens the game, it runs this new exe instead.

4.

Run the game from Steam.


If you see this screen, congratulations! You've successfully installed Kentie's Launcher. In the bottom right corner of the window, you'll see the names of the currently loaded .ini files. If you didn't install any other mods, these will say DeusEx.ini and User.ini. I installed GMDX, so mine shows gmdx.ini and GMDXUser.ini.

Enter the configuration menu, and make the following changes, as shown below:
- Renderer set to OpenGL Support
- FPS limit set to 90 (OLED) or 60 (LCD) - note that limiting the game's FPS to 50 in the Deck's Performance Settings will considerably boost your battery life
- Window mode set to fullscreen


The only thing you need to choose for yourself is resolution. The Steam Deck runs at 1280x800, but at this resolution, some text (especially commlink chat and subtitles) can be a bit small. You can also use 960x540, which is smaller but still looks good. This makes text larger, at the cost of making faces and details a bit blurrier. Some comparison shots are below, but try both and pick the one you like best.

Control Scheme

This is quite a complex game with a lot of buttons, so I made a nice control scheme which was planned very carefully. The final layout, Deus Ex by Debaser (shown below), is designed with the following features in mind. The only thing you need to do to use it is ensure that the touchpad menu buttons and "deactivate all augs" are bound in the settings.

- Allows you to move, look, jump/duck and shoot at the same time, since all of these functions are bound to shoulder/back buttons
- All augmentations bound - the most useful ones (cloak/speed/regen) bound to B, A, and the left stick respectively
- All other augs bound to the right stick radial menu, with "deactivate all augs" when you click the stick
- Left trackpad is a touch menu which gives easy access to any menu screen, as well as quicksave and quickload
- Left stick controls movement, and allows you to walk/run depending on how far you push it
- D-Pad used for rarer item functions - laser sight, change ammo, and an "alternate fire" binding which is useful for some mods. Also includes a one-button shortcut for alt-H for speedy hacking!
- Scope bound to right trackpad so you can use it smoothly while looking
- Lean left/right bound to back buttons

Other Mods

The installation process is basically the same for all mods - here are some others I tried, and the launch arguments to make them run (as well as anything else I needed to do). If you're struggling with a different one, let me know in the comments and I will look at it.

Note: Most mods can co-exist on a single installation, since they go in their own subfolders. The only exception to this I found is Biomod (Shifter), because it overwrites files in the main System folder. This means that Deus Ex Nihilum cannot co-exist with other mods, since it requires BioMod. I would still recommend copying the Deus Ex folder and using a different installation for each mod, just in case.

The Nameless Mod V1: The 1.0.4+ patch for The Nameless Mod v1, doesn't work, because it cannot detect that you have 1.0.4 installed and thus refuses to install. I got around this by just installing it on Windows, then installing the patch, then copying the TNM folder over and setting the launch options to point to TNM.ini and TNMUser.ini as normal.

INI="..\TNM\System\TNM.ini" USERINI="..\TNM\System\TNMUser.ini"

The Nameless Mod V2: This installed normally, but it installs into the main /System/ folder and does not create a subfolder, which means the launch argument looks a bit different. Main .ini file also has an unusual name.

INI="..\System\TNMDefault.ini" USERINI="..\System\TNMDefUser.ini"

Deus Ex Nihilum: This mod requires a bunch of other mods, but they're all graphical mods apart from BioMod. I installed only BioMod (by pasting it into the installation directory), and it seemed to work fine with only that one. Has a weird folder name for some reason.

INI="..\fgrhk\System\fgrhk.ini" USERINI="..\fgrhk\System\fgrhkUser.ini"

2027: Installed normally, but came with multiple renderers and Kentie's Launcher defaulted to Direct3D9, which the Steam Deck does not like. Change back to OpenGL in configuration and it will run fine.

INI="..\2027\System\2027.ini" USERINI="..\2027\System\2027User.ini"

Burden of 80 Proof: Introductory cinematic seemed a bit bugged, but otherwise runs well. Creates its own folder, but only puts maps and stuff in there. The actual ini files are in the main system folder, so the Launch Options look like this:

INI="..\System\burden.ini" USERINI="..\System\burdenUser.ini"

Zodiac: Again, creates its own folder, but only uses this for maps and places its .ini files in the main System folder, so the launch options look like this:

INI="..\System\Zodiac.ini" USERINI="..\System\ZodiacUser.ini"

GMDX v9 RSD: This is the official continuation (albeit under a different developer) of GMDX. It installs normally, although you need to apply a hotfix by pasting some files into the installation directory. However, I had a gamebreaking bug with it: Whenever I fell from height (enough to take damage), it would aggro basically every enemy on the level. If you play this mod, test this by going to the ladders at the back of the statue, jumping off them, and if you get chased by 20+ enemies, you have the bug too. I did not find a solution, but I'd love to hear it if anyone has one. Regardless, the launch path is the following:

INI="..\GMDXvRSD\System\gmdx.ini" USERINI="..\GMDXvRSD\System\GMDXUser.ini"

[Debaser]

Kentie's will definitely be possible, yeah. With GMDX I am not so sure - there are significant changes to items, perks, etc. It depends how they programmed it, since if items were replaced it will be fine, but if new items were created, you will end up with items which no longer exist in GMDX. Give it a try, and it might work.

[ilovescatsoyummy]

do you know if its possible to transfer my original save over after installing GMDX and kenties?

[Debaser]

For me, yeah. Can't guarantee it will be the same for everyone - it is a bit small sometimes, especially subtitles.

[LOID]

Text size ok on 1280x800?

[Debaser]

It's up to you. The game looks significantly better using the OpenGL renderer, because it fixes things like reflective surfaces. I run the game at 1280x800 as well, which is not possible without it. You don't need any of the other mods, though, only Kentie's Launcher. I don't think you'll find many people playing without it in 2025.

[LOID]

The game seems to just run. Do I really need to do all this? Specially if I'm gonna have to do lesser resolution for text size anyways.

Thoughts?

[Debaser]

Awesome! I am glad it was helpful for you. It might be worth checking out one of my other guides (for Deus Ex: Invisible War or VTMB), since in that I cover a different method of installing .exes using ProtonTricks. Helpful to know both methods in case one ever fails you. Enjoy!

[Crimzan]

Thanks so much for this guide!

Steam Deck is my first exposure to a Linux-based OS, and the way you have to add things to Steam in order to even run basic installers and all that jazz was (and still is) super confusing to me. I did it a bit differently, but now I got Deus Ex Randomizer and Deus Ex Nihilum running on my Steam Deck.

I'll prolly refer to this guide in the future too when I need a refresher on how this jazz works. Thank you very much for your guides and the images are all super helpful!

Speaking of which, in the "Installing Mods" Section under Step 6, "Image 11" seems to be unavailable.