Plays perfectly. There is also a native option which appears to work just as well as on Proton.
Excellent performance on dedicated and integrated graphics, and my X360 + DS3 pads work perfectly out of the box.
DXVK_FILTER_DEVICE_NAME="Intel"
The game does have a native version, but unfortunately the savefile isn't shared with the windows version, and the linux one also lacks some features. Installing the game with steam's provided proton (7.0-2 at the time this report was written) solves those small nitpicks.
minor controller problem: The Game needs to be started from Big Picture Mode with the Controller on and active, sometimes this procedure needs a second try - but it always works now.
The native linux version is now abandoned and misses achievements, but the game runs almost perfect on Proton.
(At least on Pop_Os!) The controller won't work unless you do some trickery, by that i mean, connecting the controller exactly when the game starts, else gamepad won't be detected, at least with a PDP XboxOne Controller
Native Game.
it runs actually nativly on linux, dunno why it showed here.
No issues