Algodoo

Just a simple catapult.
the green balls are "acid-bombs" and are meant to take out the infantry.
the other balls are frag-balls, that will split up into an explosion when they hit the ground.

you gotta take out the infantry, the lookout tower and the big tower, when you've done that, you get a theoretical cookie

have fun
oh, and press enter to fire, and you can steer with left - right and down to brake (bad brakes)