Thank you! Actually it's not a shader, it's sprite mask ;) 

Hi! Thanks I found that exploit too xD
Game gets harder when you reach score of 40 (or 50?). Usually our games were quite hard to grasp so we decided to do some balancing and onboarding this time. That's also probably why we slightly exceeded 3h :( .

Thanks!
Yes, that is something that is lacking in the UX department. We had to hide the color wheel because that would provide a way to cheat (you would easily see the opposite color). But after shooting 20 creatures you get access to full color wheel and you can see how the colors change in each direction.