Assassin's Creed Shadows crashes shortly after the start

[ckorn]

Compatibility Report

• Name of the game with compatibility issues: Assassin's Creed Shadows
• Steam AppID of the game: 3159330

System Information

• GPU: AMD Radeon RX 7900 XTX
• Video driver version: 1:25.2.3-2
• Kernel version: 6.16.7-2-cachyos
• Link to full system information report as Gist: https://gist.github.com/ckorn/e99ba1b1e842e27f85ae4a66801aceed
• Proton version: proton-cachyos 1:10.0.20250906-1 x86_64_v3

I confirm:

• that I haven't found an existing compatibility report for this game.
• that I have checked whether there are updates for my system available.
• that I have verified the issue is present when using Proton-CachyOS-SLR from this repository.
• that I haven't encountered the issue using an official Proton, such as Proton, Proton Experimental or Proton Bleeding Edge.

steam-3159330-native.log.gz

steam-slr-3159330.log.gz

Symptoms

The game crashes at the beginning right after the Ubisoft logo and the "HDD" warning.

Reproduction

Installed the game, the Ubisoft launcher starts, I can successfully log in and start the game.
Then the Ubisoft logo is shown. There is a warning about the game being installed on a HDD (which is not true, M2 SSD) and when I click accept there, the game crashes completely.

[loathingKernel]

The SLR log is using wayland, which makes it invalid as a direct comparison. Please test SLR without wayland.

[ckorn]

Oh sorry, forgot that I tried that flag to test HDR.

Here is the log with just PROTON_LOG=1 %command%

steam-3159330-slr.log.gz