1. install wine 9 using system package manager (9.16 worked for me)
2. create directory ~/.local/share/Steam/compatibilitytools.d/Wine-system
3. Put following files there

"compatibilitytools"
{
  "compat_tools"
  {
    "Wine-system" // Internal name of this tool
    {
      "install_path" "."
      "display_name" "wine (system)"
      "from_oslist"  "windows"
      "to_oslist"    "linux"
    }
  }
}

"manifest"
{
  "version" "2"
  "commandline" "/wine.sh %verb%"
  "use_sessions" "1"
}

9 wine-9.16

#!/bin/bash
echo launching wine "$2"
# we need second argument because steam passes "waitforexitandrun" as 1st arg
exec wine "$2"

4. run following command to make my script executable: chmod 700 wine.sh After this "wine (system)" would appear as option in compatibillity menu.

I've tried multiple proton options. 9, 8. 8-GE. Nothing work. Strangely enough wine worked for me!

Without wine game launches only first time, and crashes afterward.

P.S. Game is written in Java with libGDX, so it must be possible for author to produce native version.