Your current implementation of the Magic Staff (Description: "Restore charge of a random scroll.") selects a random staff that needs a charge, so it can be manipulated by waiting to use it at times when only the staff you want to get more use out of is charging.
Also, probably should say 'staff' and not 'scroll' in the description text :)
The x means 'I'm sure none of the current color belongs here'. If it crossed over you would have to be able to prove that no color fits in the square to be able to use them.
Excellent game, however sometimes my planes take damage from their own gas clouds (While they are dropping them.. not like, when they fly through them after dropping them)
A useful technique in war mode: Instead of trying to carefully line the bullets up with the candy, spin the candy as fast as you can. If you can complete a rotation in less time than the bullet takes to penetrate a layer, its guaranteed to strip the outermost layers first.