A game using this engine, could been you creating various set of levels using the blue and the red dots, and then the user cant move them.
But then ten the user need to been find a good place for the black + and make sure its dosent go "out of charge" too early. If its could hold onscreen in X secs, then you have won the level.
Also if you want a more complicered game, there could been more than one Black +, required to been set by the user.
This is just a game idea. The executing here is pretty nice really

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