I also REALLY loved the aesthetics of the procedural fire spreading. Something was really enchanting about the visual style overall. Great work!
A bit glitchy and I kept hitting invisible walls, so the combat/collisions could use a bit more polish, but overall the direction this is going is really interesting!
Technical notes: I definitely had better performance when downloaded vs. the web version! Might want to look into the multithreaded stuff more, because if I recall, godot web exports don't really support threads? I'm not an expert on the technical stuff so I could be wrong, but it may explain your performance drop on the web version if you were designing everything to be multithreaded