

In addition to my first report: after many more hours with the game, i decided to change some of my previous settings. I've settled on the ones i described in the first report with the following corrections:
TDP Limit - off and In game Settings (graphics):
- Limit background performance: on
- Texture quality: medium
- Animation quality: low
- SSAO Quality: off
- Bloom: off (the same goes with all other options witch checkboxes - Soft Particles etc.)
And one more VERY important thing - in order to prevent regular, severe fps drops in battles, be sure to turn off the "Auto Save" option (in game Settings - Main)!

All the issues I've experienced go away if I close the game and restart. It seems that if I don't wait for the Skip button to appear in the opening movie and press escape the mouse issues happen. If I let the Skip button appear and click it, there are no mouse issues. The sound issues only happened a few times. The performance issues only happened once. I started the game and it was lagging really bad, but again, a restart completely fixed it.
Worse performance under Proton versus Windows 10

After the release of Eldritch Realms, the game plays fine... in singleplayer. They've still not fixed the multiplayer desync nightmare.
gamemoderun %command%
Multiplayer is still completely scuffed and I don't think it's a Proton issue.
Works OOTB (Garuda/Proton9)

gamemoderun mangohud %command%
Game crashes once per 3 hour session

It runs perfectly, just as expected.
I've tested a run with around 50 rounds over several hours, and there were no slowdowns or issues on max graphics settings. It works like a charm, even during long sessions.
Worked straight out of the box on my system
The Age of Wonders games just have issues
Ran very poorly
I've played a bit of Age of Wonders 3 and it has always had issues, 4 is no different. I've tried changing proton versions and a few fixes but the frame rate for 4 was just abysmal.
Somewhat stable 60 fps @ 1080p at just the beginning of a game, but anything higher and I'd just be playing at 30. If I were to continue to play I'd have no doubt that I'd be getting 20 or less down the line. Refunded sadly.

DISPLAY=:1 gamemoderun %command%
- On startup, the game lags hard before the intro video plays; getting stuck at 1 frame until then (according to the Steam overlay) forcing me to click through them
2) The framerate is horrific at 4K on the 7800 XT even if lowering the settings from the defaults (which shouldn't be necessary for a game like this)
In multiplayer sessions, in every battle I get an odd error message about the server not being able to save the multiplayer session. Not sure if this is related to Proton or not.
Also, I was getting fequent desync messages for some reason.
I ran this in a terminal befor running the game to work around a gamescope Steam overlay bug:
gamescope -e --nested-refresh=60 -w 3840 -h 2160 -W 3840 -H 2160 -f -R --RT --force-grab-cursor --hide-cursor-delay 3000 --fade-out-duration 200 --prefer-vk-device --adaptive-sync --sharpness 0 --hdr-enabled --hdr-itm-enable

The aim here is stable 30 fps + reasonable graphical fidelity and at least 2 h of battery life. The configuration presented below mosty achives that goal, allthough not in 100% - there WILL be certain fps dips in the later game (zooming in on the strategic map with lots of animated objects revealed, larger battles) but that doesn't hinder my enjoyment of this great game.
Steam AoW4 Settings:
- Properties>Game Resolution 1024x640
- "Set resolution for internal and external display" enabled
In-game "Graphics Settings":
- Borderless, Render Scale 100%,
- Vsync, Soft Particles, Reflections, Volumetric Lightning: off
- Texture Quality: high
- Anti-aliasing: MSAAx4
- everything else: low
Quickmenu (Performance tab):
- Frame Limit: 30 fps (60 Hz)
- TDP Limit: 14 W
- Scaling Mode: Stretch
- Scaling Filter: FSR (Sharpness 5)
Battery life - approximately 2,5 h

Was working with older proton versions but started crashing after opening cutscene, experimental had same issue but 8.0-5 did not.
Has a low number of save slots per campaign that autosave will also seemingly eat up. Expect to manually delete them regularly. This applies to all versions of the game.

eval $( echo gamemoderun "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
Use the launch options to bypass the Paradox Launcher. It's only useful when using mods to select the loading order or disable some mods, etc.
30fps

eval $( echo gamemoderun "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
Paste the launch options I'm using to skip the paradox cancer launcher. It will net you 5-15 more fps. Other than that it runs faster than on windows for me since I play on low-end hardware and have more system resources available.

Seulement nécessaire de passer le launcher, unique élément bogué. J'ai lancé le jeu avec Lutris la première fois.
je n'ai pas essayé le multijoueur mais impeccable en solo quoi qu'il en soit.

gamemoderun %command%
No issues with launcher or game. Have only tried singleplayer not tried multiplayer

Occasional crashes in multiplayer.
Single player works without an issue. Multiplayer does not work with Steam default Proton or Glorious Eggroll above v7.49
No problems with singleplayer so far. Multiplayer currently not playable with Proton (Connection problems, desync, freezes, crashes).
eval $( echo gamemoderun "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
Proton 8.0-2 and Experimental tested.
Launcher doesn't show in Experimental. Launcher skiped with custom launch option.
Minor graphic artifacts on the ground with Proton 8.0-2.
Big problems with multiplayer:
- When I go in and out of the multiplayer menu, I can't get back into the multiplayer menu. For this I have to restart the game.
- I often have to press "Connect" several times befor a connection to a multiplayer match is established. Often the loading screen is displayed for a few seconds and then I end up back in the lobby.
- The message that an "internal error has occurred" is constantly displayed if I try to connect or refresh the match list.
- Often a crash report window appears, but it disappears by itself and most of the time the game continues to run anyway.
- Sometimes if I join a match the game freezes.
- If I try to join a running match (e.g. with round 70) then the game crashes seconds after I have joined.
I think proton has (only) problems with the network functions of Age of Wonders 4.
Use proton experiemental to fix crash. Set launch options to bypass (mostly useless) Paradox Launcher
eval $( echo gamemoderun "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
Артефакты на воде во время боя
Очень часто падает в меню выбора сетевой игры и в момент подключения к сетевой игре
В сетевой игре иногда перестает реагировать на кнопку завершения хода, нужно перезайти. Иногда сетевая игра подвисает: меню городов/персонажей работает, но экран по карте никак не двигается и никакие кнопки не работают. Перезаход не помогает, только начинать игру заново.
Ran perfectly, no tinkering, standard proton settings.

If you're in it for singleplayer and are able to get around the Paradox launcher, go for it.
gamemoderun %command%
Singleplayer is nearly flawless. Multiplayer is awful - requires relaunching over 10 times on average just to get in to a game (which will end up freezing within a couple hours). I have multiple crashes for each hour logged in this game.
Paradox launcher still breaks the game for me so I worked around it by making the launcher executable a symbolic link to the game executable.
No wonder the devs weren't able to get it Deck-verified by launch.
Can't interact with main menu and then fades to black
Game launches but can' t play it
Game did not launch with Official Proton 7, works flawlessly with GE-Proton7-55.
eval $( echo gamemoderun "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
Z-fighting amongst terrain textures, settled city field textures, and shadows
The launcher won't work under Experimental Proton but will work under 8.x.
The game will work under 8.x with very obvious texture and shadow problems near settled cities.
The game will work under Experimental Proton with shadow problems.
Run under Experimental Proton without the launcher and turn shadows off in the graphics settings for an excellent experience.
Works out of the box, which is mighty impressive for a new game.
Flickering textures
Played it for a few hours until I had a single crash. All problems experienced are identical to those reported on windows, so whatever problems there are, they are "new game" related rather than Linux related, except that I cannot switch to fullscreen so that I could lower resolution since my 8-year old graphics card can't handle 1440p.
Running it in game mode is mandatory because its CPU hungry, which is again nothing different than how it would be on windows.
No problem with Proton 8.0.2, launcher not working with GE-Proton8-2.
Paradox launcher not working with GE-Proton8-2, only offering an "exit" button to close it.
No problem with Proton 8.0.2.
eval $( echo VKD3D_CONFIG=no_upload_hvv PULSE_LATENCY_MSEC=90 "%command%" | sed "s/launcher-se\/Paradox Launcher.exe'.*/AOW4.exe'/")
With stated launch options, runs fine. Late game can dip to 40fps though
Crashed once in 7 hours playtime
Very buggy, framerate dips to 20s in the late game
Unplayable bad vanilla performance
Serious framedrops and slowdowns from Low to Ultra presets. In battles slowdowns is even more noticeable.
You should wait for driver optimization to play this game on Intel Arc. Now this game is barely playable
Minor artifacts with some glow effects on the world map.
For Proton to successfully install the .NET package, I had to forced Steam to use Proton 4.11 on the first launch of the game. Then, for better stability and perfomance, I set Proton to version 8.0. Since I first tried to install with the latest version, as suggested by other reports, I had to delete my compatdata/1669000/ folder to force Steam to create a clean compatdata for the game with Proton 4.11; setting it to 4.11 after a .NET install has already failed with a more recent version does not recover the situation.
gamemoderun %command%
Launcher would crash without Proton 8.0-2
Game ended up not being for me so I don't have hours in it - but the bit I played everything was fine once I switched to Proton 8.0-2
VKD3D_CONFIG=no_upload_hvv %command%
VKD3D has massive problems with resizable bar.With ReBar Enabled, there are strong framedrops in the campaign card as well as in the Battles and when opening the hero menu the game crashed sometimes. With the following command base in the Steam start options, the game runs very well and stable at 70 -90 FPS at 1440p Ultra. Vkd3d_config = no_upload_hvv %command % Video: https://www.youtube.com/watch?v=_HHx6LnK9wo
Frequent stutters while moving around, similar to Victoria 3 (although they use completely different engines).
I tried several things:
- Change to Proton 7.0-6: Paradox Launcher works, but the game crashes a couple of seconds after starting
- Change to Proton 8.0-2: still stutters
- Use AMDVLK 2023.Q2.1: less stutters but worse performance in general (AMDVLK shader compilation still bad).
- Use AMDVLK PRO 22.40: way less stutters, better performance, lots of artifacts in the UI.
CPU utilization never go past 15% and GPU utilization sits at 70-80% most of the time, which just points to bad optimization, so there's not so much you can do about it.
Badly optimized in general but runs fine on Linux, no crashes so far.

Did not test Experimental proton, may have lunched with it.
Worked well once I selected Proton v8. Rare crashes when saving or loading to frequently. Multiplayer doesn't work.
Rare crashes when loading or saving games.