


Runs great in proton, avoid the native version
I had trouble getting the native version to run, but when I did it ran fine. The only issue was that I could see graphics outside of what I was supposed to see on my ultrawide monitor. The Proton version didn't have this problem. After I played the native version, I couldn't get it to run again. The game uses Unity for saving your game data on Linux and the registry on Windows. This meant that I was unable to transfer my savegame from the native version to Proton, requiring me to start my whole game over. Luckily the game is pretty short.

Though Pony Island has native version and it works in most cases, the scene with asmodeus would glitch a bit (won't affect gameplay), and it's unplayable if you need to use input methods (e.g., playing with language set to Simplified Chinese).
Proton works well at first glance, though it looks too much trouble migrating savefile from Linux to Windows (registry) so I didn't test through the whole game with Proton.
Game works just fine. Did not get any issues during gameplay.
Game starts in fullscreen at the lowest possible resolution.
I did not get the audio problems that others have reported.
I did notice that the game does seem to use ALSA so having the configuration package for your sound server installed or just using pure ALSA would probably fix it.
pipewire-alsa
is the package for the PipeWire ALSA configuration on Arch Linux.

No sound in native (I use pulseAudio) Work great with proton
Does not start on my main monitor, but on another monitor

Play through Proton, not the Native version.

Game works as intended without any issues. Proton Experimental
Half Rate Shading, 300 GPU, 60 FPS Limit
Some text doesn't render properly in 1280x800, changing the resolution to 1280x720 in game fixes it. Game is still technically completable if you don't, but would be confusing to a first time player.
The native version worked OOTB. I haven't encountered any problems
Text wasn't small, but the in-game chats are misaligned and not readable
Being unable to read the chats makes the game unplayable (at least the first part of it)
Native version didn't start at all. Crashed right after launch.
Pony Island doesn't seem to like being played in 16:10 and has some minor text issues because of it.
Better than native
Sound wasn't working on native, so I ran it through Proton and everything worked perfectly.
Worked perfectly throughout the game without alteration

6.20-GE-1 GloriousEggroll
Proton-6.20-GE-1
Native build did not have working audio; Resolution detection was also not working (i3).
Both work great on Proton Experimental.