This is a very interesting mechanic. I have some issues, though:
- I do not like that you have to select a color when you only have one
- The collision box for the ghost (white) enemy is too large. And why can't I block it with white paint like I could block the black enemies with blue paint? It doesn't make a lot of sense.
- Why use a dedicated button for jumping? Why not use the up arrow. It will make the game a lot easier!
- Maybe add a limit to how much you can paint with a given color to give a bit of extra challenge.
Overall it is a nice game! I enjoyed playing it.