the reason its anoying is the graphics go haywire But i know exactly how to trigger this all you need is a way to get a piston slime blocks redstone and a way to reapeat the procces (rapid repeater works best) get it to turn on then stand under it... the results should be you moving on top and below EXTREEMLY fast. I think the reason is that the game for some reason get confused weather your on the slime or not, or maby the game thinks your a block, but thats all i can come up with