That was really refreshing. The core mechanic is really interesting and engaging, I liked it a lot, it's really good for a prototype that you could develop further. The bosses were entertaining, and while their mechanics were simple, that allows you to focus more on your colors, so it works really well. As others have said, it lacks visuals, but that's something that can be fixed down the line, you have the proof of concept of an interesting idea, I hope you can continue to develope it in the future!