using negative values of vx and vy is advisable as positive values will only cause a one pixel thick layer of sponge facing the direction of motion to fly outwards.
it is also stackable in that you can get sponge to fly diagonally. however, whenever you load a save, sponge can only move at speed 1 regardless of what you initially set it to.
you could theoretically do this to every element, but spng is the only element with a visible response. goo just deforms and the other elements just do not move.
Actually, this guys new, cctv just takes advantage of new users, when you were first born would you like to be made fun of because you couldnt walk well?