The idea and the bosses are really cool. I think it's interesting to throw a ball at the boss and then have to go get it again, and I like that each boss has a completely different attack pattern, so you have to wildly adjust your strategy and expect the unexpected.
Overall, I really like this game, good job!
(Also if you have a free moment, I would really like it if you could give me some tips on my game, I'm planning on remastering it and possibly selling it on Steam, so any input would be greatly appreciated)