I had a lot of fun with this game! I really loved the art and sounds!
The coordinated color attacking mechanic was really fun too. I was confused at first on how to attack after selecting the color so maybe an indicator on pressing the spacebar to fire the attack would be useful. I did read it from the instructions too so that definitely helped!
Also when the 2-color enemies appeared, I mistook it to mean mixing those 2 colors together instead of attacking with each color individually. I'm not sure how to go about it but that would also be useful. Maybe show 1 color at a time, but show the other color stacked behind it?
Overall though, very fun game! I get scared when the monsters get too close haha.