heyas; first, get rid of the sphere. if the box is opaque, you wont see it, you don't need it. then, obviously, it won't poke through the box ;) second, slap some magnets on that box, there. use them to create bulges where the 'ball' is bouncing against the square. you can spawn morph targets with the magnets, or just animate the magnets, depending on how much tweaking you want to do of the positioning of the bulges. don't say "d'oh!" it really isn't that hard. ;)