If you read the issue for proton on Github, you can see that it is possible to start the game, but there are many issues and performance is pretty bad. A lot of work is needed for this to be be really playable.

I’m keeping an eye on this. Even the Windows release was far from stellar, so I expect it will be some time before the port is stabilized and we can rely on the Proton reports for the current state of the game.

The game is a mess on PC. It's a bad 3rd party port, horribly optimised even for Windows, and probably won't see decent performance on Linux until later on in the patch cycle. See the Digital Foundry videos for more info

It seems it works with Proton 5.9-GE-6-ST: https://www.youtube.com/watch?v=8KVrk5GTl1Q

I got this game with amd rewards. Tied it with Proton 5.9-GE-6-ST only for about an hour or so. The open mesa amd drivers do work but there are rendering errors; artifacts and vertex explosions, also the performance is okay but still sub par.

I then tried the AMDVLK drivers just to see, and they rendered and performed well, although I have just now experienced my first crash.

Does AMDVLK driver is include in Mesa 20.2 driver ?

The new release of Proton seems to fix some issues for this game. Can you test it?
https://github.com/GloriousEggroll/proton-ge-custom/releases/tag/5.9-GE-6-ST

Last edited by Vinouch on 20 Sep 2020 at 10:27 am UTC

The AMDVLK is part of the closed source driver. You will have to check your package manager or ppa to install it, you will then need to add these launch options to the game

VK_ICD_FILENAMES="/usr/share/vulkan/icd.d/amd_icd64.json" %command%

It will rebuild the shaders on relaunch so you can expect a slow start for the first game, but after that it seems to run well.

Personally I will be waiting a little longer for the mesa drivers to overcome its issues with this game before I give it a proper play through.