It appears a message about graphics and directx. Nothing works.
Disable force composition pipeline
option with nvidia-settings
Works fine

OPENSSL_ia32cap=~0x20000000 %command%
Black screen on the next launch after the first launch and so on
gamemoderun %command%
Runs perfectly

Clear, just select proton experimental in properties -> Steam compatibilities -> Proton Experimental
No problem, it's works !

Was able to play through the tutorial and get into a multiplayer game without issues

Works straight out of the box. No issues other than one easily fixable bug.
If a new savegame is created twice in a row, the world generation stops the second time and the game has to be restarted to create the new savegame.

Perfect
I haven't noticed any problems, it works smoothly.

PROTON_USE_WINED3D=1 %command% -useembedded
If you are in dual-boot mode, you may find, as I did, that the game launches without displaying the game window. Windows may block protondb files as a ‘serious threat’. All you have to do is run a full scan with the Windows antivirus and then authorise the ‘threats’ containing the links to Steam.

Plays smoothy with GE-Proton8-23. No launch options needed. All other proton versions would not launch the game.

Strange bugs with the Steam interface but the game itself runs flawlessly.
Seemingly at random, launching the game will cause Steam to load and reload itself, open random menus, present seemingly unrelated error and other messages, change its interface settings and generally glitch out. Ctrl+Alt+Backspace will stop this, but you cannot start the game again without a reboot. Additionally, do not attempt to use the Steam Overlay (Shift+Tab), it will cause the game to crash.
Oddly enough, even if the above glitch happens, the game itself is completely playable.

Long first launch. Compatdata can take few Gigabytes for generated map.

Everything works but on 12th gen i7 I needed the launch option to use 64bit version of EL.
OPENSSL_ia32cap=:~0x20000000 %command%
Massive FPS drops during dust eclipse (DLC), had to disable them. Also to install the ELCP community patch, run Explorer from protontricks prefix, then choose ELCP executable: protontrics 289130 --gui
Works without any issues out of the box
EL+ELCP mod worked great with Proton Experimental. No STEAM Launch Options were required with this hardware config using Linux Mint 21
No Launch Options required for Max settings with FPS +72hz using Proton Experimental on this hardware. I did have to tinker with Linux Mint 21 to get my AMD R9-390X gfx card to use the [amdgpu] linux graphics driver, instead of the older [radeon] one, which was causing problems in some games.

WINE_CPU_TOPOLOGY=5:0,1,2,3,4 %command%
Apparently there's an issue in some Unity games where if you have many CPU cores, worker threads gets assigned to all of them, but not given thread priority, resulting in slowdowns. This is fixed on this title with the launch argument that assigns five cores.
This report includes using the ELCP mod V2.7.8 ; instructions for how in link below: <a>https://youtu.be/HeeBFZJ-9ro</a>
PROTON_USE_WINED3D=1 %command% -useembedded
EL+ELCP mod can be done in Linux! See my YT video for a how to guide.
-useembedded
Maybe I need some more clicks to make audio clear
OPENSSL_ia32cap=:~0x20000000 %command%
I had to add the command to stop the game Crashing to Destop after the splash screen. This apparently fixes an issue for certain generations of Intel CPUs, so you might or might not need the command depending on your model.
Game closes immediatly at the loading screen, no matter what protonversion is used.

Works but has like on Windows a bug that makes it crash on startup. Possible workaround in the notes.
The game crashed on start regardless of running it under Proton or Windows. Took a while to figure it out but apparently it's a bug with OpenSSL on Intel CPUs of generation 10+. There are two workarounds:
- Play without an internet connection
- Do a little tinkering in the registry (for Proton)
For the latter:
# change from PATH_TO_WHERE_YOUR_STEAMAPPS_FOLDER_IS to the right path for your system
# I'm assuming here that you are using Proton 7 but you can change that too
# Execute the following line in a terminal to open the registry editor
WINEPREFIX=PATH_TO_WHERE_YOUR_STEAMAPPS_FOLDER_IS/steamapps/compatdata/289130/pfx PATH_TO_WHERE_YOUR_STEAMAPPS_FOLDER_IS/steamapps/common/Proton\ 7.0/dist/bin/wine64 regedit
# In the new window that opened you should navigate to
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment
# and right-click -> new -> string value
Value name: OPENSSL_ia32cap
Value data: :~0x20000000
As per link from above, setting this "[...] disables the OpenSSL code check for SHA extensions and runs a different code path that does not contain the crashing bug"
Switched to 32-bit version
Works fine in 32-bit, but since 64-bit crashes after the title splash screen, I can't use the Endless Legend Community Patch to help with the game balance.
The logo screen appears then the game immediatly closes
The game installs just fine and when running the game the inital videos play and then the logo screen appears. After that the game immediately closes
Perfect experience.
Occasional full-screen glitches for less than a second.
Worked out of the box
Worked like a charm
very pleasant experience
The problem was in creating the map, I use the "World Generator Full Customization". I usually create a map with a width of 200+ and a height of 150+ (endless+). On windows, it takes about 5-8 min. Here, I spent 20-30 min creating, but then absolutely no complaints p.s. 70% land,the rest is default

PROTON_USE_D9VK=1 %command% -useembedded
The game crashes on vanilla run, requires "PROTON_USE_WINED3D=1 %command% -useembedded" to be used. Afterwards runs ok, with minor audio stuttering issues here and there, mostly in cutscenes.
Minor stuttering and skipping
PROTON_USE_D9VK=1 %command% -useembedded