Linux does not run Windows games directly. Several pieces sit between the game and your hardware, and a report that names the wrong one sends people chasing the wrong problem.
Wine
The foundation. Wine translates Windows API calls into their Linux equivalents at runtime. It is not an emulator — there is no virtual machine, and no copy of Windows involved.
Proton
Valve's distribution of Wine, bundled with Steam. It adds the graphics translation layers below, plus per-game fixes. Versioned like 10.0-3.
Proton Experimental is a separate, rolling build that changes far more often. If you are reporting against it, say so and give the date — "Experimental" on its own does not identify a build.
Proton-CachyOS is CachyOS's own build; the BlizzNux Launcher uses it when it is installed.
Proton-GE
A community build maintained by GloriousEggroll, with media codecs and patches that Valve's build does not carry. Versioned like GE-Proton11-7. Frequently the difference between a cutscene playing and a black screen.
Source: https://github.com/GloriousEggroll/proton-ge-custom
umu-launcher
Runs Proton outside Steam, inside the same container (the Steam Linux Runtime) that Steam itself uses. This is what the BlizzNux Launcher uses to start Battle.net. It downloads that runtime the first time, about 660 MB.
Source: https://github.com/Open-Wine-Components/umu-launcher
DXVK
Translates Direct3D 9, 10 and 11 into Vulkan. Most older Blizzard titles go through this path.
vkd3d-proton
Translates Direct3D 12 into Vulkan. The newer titles use this one, so it is usually the relevant layer for Diablo IV and Overwatch 2.
Mesa
The open-source graphics driver stack for AMD and Intel. Your Vulkan support comes from here, which is why a Mesa version belongs in any report on those cards.
NVIDIA
NVIDIA ship their own proprietary driver with its own Vulkan implementation. The open-source nouveau and the newer nvidia-open modules behave differently again — say which you are on.
Why the distinction matters
"Proton 10 works" and "Proton-GE 11-7 works" are different claims. So are "Mesa 25.2" and "NVIDIA 580". A report that omits the layer is one someone else cannot act on.
