Art is really good, everything has lots of great visual feedback. Also just the art in general and the lighting looks good. Same deal for sound. Stuff like having a different attack swing, hit, and kill sound improves the experience. Music works well for the dark exploration vibe. Game elements were introduced well from a design perspective. Ending sequence was nice.
One minor nitpick is I would have liked a "healed" sound. I did not notice I was being healed until pretty late. Oh also you probably shouldn't need full-screen to specify a particular resolution. You can get a particular resolution by usuing a Canvas Scaler component set to "Scale with ScreenSize, switching to minimal player in the player settings tab of build settings, and specifing the desired resolution in itch's game settings.