Simple and short. Loved the cover art of this and the general idea. At first I was like "why is there no sound" and then I realized why you chose to go with no background music. A couple of things I think could help this and could be helpful in your future games: 1 - A full screen mode. It's easy enough to add in godot, and would make the buttons and text easier to read than in the browser. (I'm just assuming the download version does this by default). 2 - Maybe a few sound effects for when you move or the creatures move or when you click the menu button/switch instruments. I'd always try for audio and visual feedback to any interaction the player takes.
Still, a solid entry for a first game. Bonus points for going with isometric 2d art (I've been reluctant to try that, lol). Congrats on the game!