


Both Native and Proton versions are unusable on Wayland
Using native version I could get it to boot into the game when using GL instead of Vulkan, however performance was so poor that it was not worth mentioning. On vulkan the game would just crash on the loading screen, regardless of settings.
On Proton (using unstable) I could get the game to load 1/25 times, however there was no rhyme or reason to when/why it'd work. Usually it just blackscreens directly upon launching.

Only works under GE-proton10-9 and NOTHING ELSE. Otherwise warns to check game files and install DLLS
Gamemoderun %command%
Game stutters significantly more than on windows, and after 1-2 hours, it slows to an unbearable level until reatart
Game crashes relatively frequently, but this is a common issue on windows as well.
Any other version of GE proton fails just like proton main. Native also works but is just a buggy mess. I reccomend playing under GE but expect signifigent performance issues; typically solved with a quick restart

Runs Natively on Linux however Proton Experimental and GE-Proton provide better Framerate and Stability especially going into the late game

It's CK III. If you're into it, you'll put up with the crashes. But it's more of a struggle than with CK II.
Switching to Proton 9 from native.
It "runs" natively on Linux, but crashes frequently. It still crashes on Proton 9, but less so.

Set ZRAM and SWAP to 8GB each
Performance issues when zooming out and in courtroom.
The game takes up a lot of RAM, so your RAM should be big or you should allocate more ZRAM/SWAP.

Нативна підтримка ідеальна
Мультиплеєр погано працює. Я бачив, начебто це через поєднання Lunix та Windows гравців. При заході другого гравця і запуску часу, гра десинхронізується. Це відбувається виключно після намагань продовжити гру, яку ви зберегли.
Протон не потрібен

corefonts vcrun2019 d3dcompiler_43 d3dcompiler_47 dotnet48
When launching through Steam or Heroic, it would not see the saves in the ParadoxInteractive folder
Game did not start without upping Swap Memory to 16 GB

Forcing Proton Experimental makes the game run as well as it does on Windows with great performance and decent loading times. But using the native Linux version of the game was not a great experience. The FPS was borderline unplayable and there were a lot of rendering glitches, no map textures would load and fonts were all mixed up. Loading took ages. Apparently officially they only support Ubuntu-based systems with the native version.

The game basically eats all your RAM. I had to increase the swap memory to 1.5x my RAM in order to pass the loading screen.
Increased Swap to 1.5x RAM
If you don't have much RAM, you can increase your zram editing your /etc/systemd/zram-generator.conf file. Do not go crazy with your zram as it will drain your CPU performance.

PULSE_LATENCY_MSEC=60 gamemoderun %command%
5-20 fps
Menu navagation often causes the game to crash
Both the native Linux version and running through Proton resulted in terrible performance. Gamemode did not help. Common tricks like setting performance modes also did not help. Had to use PULSE_LATENCY_MSEC=60 to keep audio from breaking

All Gucci

big ass memory leaks g
Not so Gucci now

After 1.16 on Linux, there are major memory leak issues that need to be patched.
I think this is mostly due to the entire system freezing up.
The game kept freezing my entire system, requiring a hard reboot.
If my entire system didn't freeze, the game would crash and be killed by my kernel due to memory issues.
Both the native and proton versions had memory leaks when launching the game and are unplayable.

I tried it both native and with proton, both work but have their own problems:
Native runs better 90% of the time but laggs whenever an event that uses more then one 3D character model happens.
Proton: runs slightly worse but has no lag spikes.
But generaly the game is playable, windows also has ocasional lag spikes depending on the update of the game, so I'd say it is in a good state to run on linux.

Can work given you have enough ram and swap. Deleting vulkan cache in Paradox folder can also fix some crashes when updating.
Faced unfixable frequent crashes. Increases swap space to 2x my ram and finally the game runs smoothly.
Crashes were frequent and only went away when increasing swap space to 2x my ram.

J'ai 16GB de RAM dont une partie est utilisé par le GPU du processeur, cependant j'avais un crash au lancement du jeu (en natif comme avec Proton comme avec des anciennes versions du jeu). Le problème a finalement été résolu en ajoutant une partition de SWAP de 16GB de plus pour ne pas crasher par manque de mémoire. Je vous conseille donc de ne pas lésiner sur la SWAP en swap file ou en swap partition pour ne pas crasher.
Läuft problemlos nach Installation

Eats all VRAM and then system slows down
making the game unplayable, giving like 5fps both in menu and on the map. when running non-native via different proton versions, launcher isn't able to run the game suspecting game crashing. can't find any logs.

Great experience OOTB after waiting to load
Max resolution is 1080p although I play on a 4K screen.
While loading the game I keep getting 'Game is not responding' messages but after finishing loading game runs perfectly fine.
I don't know why but can't bump up resolution higher than 1080p...

The game is unplayable on systems with less than 32Gb RAM.
Frequent out of memory kill crashes
The game eats up all of your GPU memory on start up and when there is no VRAM left it starts to consume your system's RAM. It seems like the game loads up all the textures and other graphical stuff into the VRAM and system memory which is clearly a bug that was not present until some update about a year ago.

Don't waste your time unless you have at least 32G of RAM, the game consumes almost all of your PC's memory.
gamemoderun %command%
Memory drain
There is a problem with RAM consumption, for now even going to previous versions of the game will not solve it.

Tried it with Proton first, and it loaded smoothly but had some lag when scrolling around the map, and also a random crash (though tbf Windows also has random crashes). Native a bit laggier than Windows, but generally solid performance. Much faster load times either way, even with a relatively heavy modlist

-noasync -debug_mode
постоянно после старта игры спустя пару минут начинались сильнейшие лаги, зависание и краш игры (время начала этих лагов всегда было одинаковым после старта игры)
P.S. если кто знает как исправить прошу написать мне в дискорд: ellistab2

Without tinkering the game crashes when starting the game, seems to be a memory leak that completely fills the RAM.

DRI_PRIME=1 DXVK_FILTER_DEVICE_NAME="AMD Radeon RX 7700S (RADV NAVI33)" %command%
Specify dGPU. Select Proton 9.0.4+ (Experiamental)

-noasync
When I ran it out of the box I was not able to play past the quick tutorial. But after tinkering no problem what so ever

gamemoderun %command%
Disabled animated character portraits since it caused an incredible lag for some reason. Works fine with Vulkan as renderer
Game is lagging hard with animated character portraits
KDE Plasma crashed at least once while playing. Impossible to open new Firefox window or use the existing one after a few Alt-Tab's

Rare crashes

SDL_VIDEODRIVER=x11 gamemoderun %command%
Fullscreen is oddly slow
You only need to add ncurses6 to your programs.steam.extraPackages otherwise it would fail to start.
Running SDL with the native Wayland backend will also not work, so if you're like me who uses Wayland-everything by default, you need to set SDL_VIDEODRIVER to x11 for the window to behave properly. Otherwise, everything should just work!

I had alot of issues making this work - my problem seemingly was the launcher either not showing on proton versions lower than 9 or just flat out freezing after launching on 9 and onward
Found out there has been a documented issue of playing the newer versions of the game after 1.10.2 (https://forum.paradoxplaza.com/forum/threads/known-issues-1-11-1.1612687/)
I found this suggestion on the paradox forums (https://admin-forum.paradoxplaza.com/forum/threads/game-doesnt-start-linux.1702216/)
Which led med to installing the steam client directly from steam rather than flatpack/PopOs! - that made everything work and it fired without issues the first time after installing
Milage may vary - best of luck <3

Spent a few days fighting an "Unknown error" when trying to login to paradox on the main menu (not the launcher). But eventually just ticked the "Force use of compatibility tool" on steam and it worked straight away!

-noasync
Multiplayer with Windows machines results in a near immediate error after trying to start the game at normal speed. Error listed was for CoatOfArms. Switched to Windows install and same save works fine.
Stable for single player - issues with multiplayer (Windows users)

Game uses all RAM (14+ GB) and completely freezes the system.
Probably has a memory leak or something, but is unplayable with 16 GB of RAM.

Change install drive to main ssd
Worked perfectly out of the box on my AMD APU laptop (Fedora Linux)
On my Intel cpu + Nvidia gpu desktop (also Fedora Linux), I initially installed it on my secondary ssd which led the game to be completly unplayable. Extremely messed up graphics and frame rate. Putting the game on my main ssd somehow fixed it
Also Vsync keeps limiting my fps to 60 despite my 165hz monitor, but this seems to be an issue with almost all my Linux games
SDL_VIDEODRIVER=x11 %command%