


Sometimes the game's FPS drops. This doesn't happen all the time. The game itself is not very well optimized
Overall, the Linux version of the game runs significantly better on the Steam Deck than the Windows version via Proton. In the native version there is no FPS limit to 30, and the FPS itself is higher. However, it is rare, but it happens that FPS can drop - this is especially noticeable in massive battles
As long as multiplayer with a Windows player isn't required, it's playable from my experience in a few hours of solo campaign.
Native version is not the same as Proton/Windows version, appears to be behind? Saves from Native can be loaded in Windows, can't do the same the other way around.
Starting game, starting a dwarf campaign, and doing a few hours of gameplay including battles went without hitch on default native. Pesky save and multiplayer version issue keep it from being perfect.
Proton version has nasty once-per-second hitches in the campaign map on all version I've tested so far (>=v7, including experimental and GE) that make it unplayable for me. But it's the only way to have "cross-platform" saves. So either play native version only, or don't play on the Deck unless you can handle the hitching.