Click it to get it going. When it stops, click it again.
This took way longer than it should have and would have had more things, such as continuous bouncing, shadows and reactions of the targets (If you look inside you can see the reaction costumes). I got sick of working on it and shared it. ~EDIT~ The bouncing is now random! Please notify me of any glitches. Hey, if you're reading this, please know that this is super old.