Hello @Deckweiss, you may have better luck with nvidia 396.54 or newer.
Additionally, if dxvk is being used, then the game may be tripping over mesa/Intel/Haswell's incomplete vulkan implementation. You could try temporarily disabling intel vulkan support by moving /usr/share/vulkan/icd.d/intel* somewhere out of the way.
Also, there are some Proton runtime options you could try out.
I updated the nvidia driver to the suggested version and encountered this problem: https://github.com/ValveSoftware/Proton/issues/65
So I can't confirm if it works until optimus/ primusrun/ optirun is working for me
Compatibility Report
System Information
I confirm:
Proton Log
Symptoms
When I run the game it shows an Error prompt with:
"Legends has encountered an error and must close.
A crash report named "Crash_2018-10-03-133856" has been generated. These files can be sent to Bethesda Softworks LLC for analysis. Would you like to open this folder now? Yes/No"
When I open the folder there is an error.log and a crash.dmp, but I cannot upload the dump here.
error.log
Reproduction
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