Cool concept, I’ve always wanted to play some kind of rhythm based twin-stick! It’s a little strange to hear the musical note get played in an unrelated key while the background music is playing in a different key. It might be worth pitching the ‘shoot’ musical sound effect up and down based on the background track to make this a bit less discordant. Also, maybe it was just the web version, but I felt like the shooting rhythm didn’t always match that of the music.
I ended up dying at the 3rd boss unfortunately, but I got close to beating it! I liked the different spirits, I was pleasantly surprised that they all had really different effects (especially the healing spirit). Nice job! I like the gungeon-inspired art style too.