Hate to say it, but I refuse to buy games on other storefronts since I got the deck (I love the drm-free aspects of gog). Until other companies put in the effort to support Linux, I don’t see how they deserve my money.

Interesting. What works for me is an install from Heroic, adding exe to Steam, and also a flag –skip-launcher for it. AFAIK .NET is only needed for the launcher.

cause DRM free yay!

BG3 doesn’t use Steam for DRM, only for distribution. You could zip up the game’s folder and burn it on a million floppies or whatever, and play the game wherever you like.

Have you tried adding it to Steam as a non-steam game and then forcing compatibility for it to proton experimental in Steam?

Try Bottles. Lutris almost never works for me, Heroic is a bit better. But once I discovered Bottles, I’m basically never using anything else. Bottles can also automatically add an entry to Steam for your game. So any non-Steam game on my steamdeck is via Bottles.

It broke for me because gustav.pak was missing. Might be the sameissuee for you or something similar. Try repairing the game with Heroic. If that doesn’t work (didn’t for me because of space), try downloading it on a different PC and copy the files on top. That fixed it for me.

Also, disclaimer that this just worked for me and I can’t guarantee anything.

Are you downloading it directly from GOG? Have you tried installing other games? I see you’re going to try lutris, which may work better. I use Heroic Games Launcher which works like a dream for both gog and epic. Have not tried Baldur’s Gate 3 through Heroic though.

A recent thread on Reddit seemed to help some folks: https://www.reddit.com/r/SteamDeck/comments/15hg5ta/gog_version_of_baldurs_gate_3/

I got it working, I intend to buy the game on steam next payday (this week), until then I’ve borrowed the GOG version from a friend.

1. I had the already installed files.
2. I copied them over the the steamdeck, I picked /run/media/mmcblk0p1/steamapps/common/ to put the game, so it’s stored similar to other games which are on the sd card. I use Linux on my main computer so I used rsync to copy it over. With SSH enabled on the steamdeck it was something like rsync -r -azvhP "Baldurs Gate 3" deck@192.168.0.15:/run/media/mmcblk0p1/steamapps/common/ It took ages, maybe a few hours, I played Hades which I usually play on 3W TDP, I unlocked the TDP while playing Hades in game mode while copying the files, and Hades was stored on the same SD card which I was copying BG3 to. Hades just had slower loading times.
3. I added a file called steam_appid.txt with the contents 1086940 only that as the contents, inside /run/media/mmcblk0p1/steamapps/common/Baldur's Gate 3/bin/ next to the bg3.exe file.
4. I have GE-Proton installed. On my main comptuer which uses Arch I just have the AUR package installed, and it only keeps the newest version of GE-Proton. On the SteamDeck I sadly use ProtonUp-qt instead to update GE-Proton.
5. Added "/run/media/mmcblk0p1/steamapps/common/Baldur's Gate 3/bin/bg3.exe" as a non steam game in desktop mode, remember to double check that the quotes are added, if not add quotes to the beginning and end of the string after wards. pick bg3_dx11.exe instead if you want the dx11 mode.
6. Set GE-Proton as the compatibility mode.
7. Go to Game Mode and try to launch the game. It looks like it doesn’t work, because the game doesn’t show up in the foreground, but if you press the steam button, so the left side menu shows up where it says Library, Store etc, the game is running and is in the list Above Library, so I can pick return to game or something.

Bonus step (settings), I also added the mod that replaces DLSS with AMD FSR2, and I run everything at low, except shadows, and have TAA + FSR2 with the wrong name for the profile called Ultra Quality. I have the game locked to 30fps in the Steam Deck quick access menu. I am okay with 30fps, and I prefer to have a slightly longer battery life than eking out the very last bit of performance or visuals out of the game. It’s a bit blurry, but I found these settings were quite nice. Wish I could have higher texture settings, but it seams to not load in higher textures even if I try to pick it, since it looks like the VRAM is filled up without it. The menus are at native resolution, and the faces of the people seam very nice with these settings, so I call that a win. I have not tried DX11 though. Slow HDD mode seams to not work, as it should load more things into RAM to reduce issues with loading from a slow disk, but the memory and vram is already filled so It doesn’t seam to give better performance. Anecdotally turning off Slow HDD mode might reduce some frametime spikes, not sure.

Note, Since I intend to just buy this game this week, I think I’ll just start a new game, but if I wanted to copy the save game files over, I would go to ‘/home/deck/.steam/steam/steamapps/compatdata/’ find the randomly generated ID for the non-steam-game, would start with checking the most recently updated folder, enter that directory, then pfx/drive_c/ and look for the same game, and copy it over to the compatdata folder for the steam version of the game manually.

Do you have anything else installed that might interfere with the game ? In another thread I saw someone have issues due to stream deck tools. Some launcher mods ?

Try using heroic launcher.

Lutris?

Haven’t tried with BG3 but I’ve had great luck with Heroic Game Launcher.

You’ll need to use desktop mode to install it and add steam shortcut. You might need to run Winetricks inside HGL to install latest version of MSVC and . net if it doesn’t launch.