Introduce you to a very simple form on the ball, which is different in color from the others, but it costs you only activate it at the same moment to explode and smashed into several fragments, and if one of the fragments fall into the other balls they will be the same in color and explode ! But there will be more balls and hidden that will appear after the destruction of the first and you have to think as well that would blow up and they came under a blast!