need help w/ Worms Game with backgrounds and explosion

[AsianSensation]

So far, i can hold down a weapon, see how long it took, and fire it w/ velocity increase accordingly. Then there comes a problem: if the missle hits the ground, then it explode, and changes the terrain, how do i make this thing explode so I don't have to cls and redraw the background. I saw the previous guide, but it kind of doesn't work here, for my picture is something like 1600 x 400, pretty big to separate into different pixels. appreciate any help from any one.

p.s. once i am finished, i'll be able to release the program to the public, and let people play around and see if there is any bugs with it, that is, IF I finish.

[Tony]

well you can cut it into bigger pieces. I donno, 10x10 pixels?

the only problem would be that craters would have squares for its edges. I suppose to can cover that with transition drawings of fallen earth? Like slopes or something.