Tiny Auto Knights is an upcoming release from Mumpitz Games with a demo now available that now has Native Linux support for it. Seems like a nice way to spend a few hours, if auto battling PvP is your thing.
A little more about it for you: "Recruit heroes with unique skills and place them strategically on the field. Merge the same characters to level them up and get access to more powerful skills. Optimize your team and create strong synergies. When the battle starts, your characters will fight automatically and use their skills. Where they are on the battlefield determines the order of attacks and skills. Status effects like armor, poison, or bleeding make the combat even deeper.
Win battles to earn Unlock Tokens! Use these tokens to get new characters and add them to your custom deck. Find unexpected combinations and perfect your strategy. Share your decks with the community and friends ‒ and try out their creations."
Check out the trailer below:

Direct Link
Speaking about making it supported directly on Linux the developer noted how "It was running quite okay with Proton before, but I could see performance improvements (more stable FPS and less fan noise) on my very old Laptop (Intel i5-4210U, AMD Radeon R7 M260) running Lubuntu 24.04.3 LTS with the native build".
Game Highlights:
- Play against teams of other players: Discover and learn new strategies
- No turn timer: Take as much time as you want
- Ranked and Casual mode: Play competitive or have a relaxing time
- Compete in weekly challenges: Find the strongest build from a curated deck
- Find relics: Get passive bonuses to complement your team
- Create custom decks: Choose from dozens of unique characters