Algodoo

This is simply 4 ballistas (basically big Greek crossbows), each aimed
perfectly at a building, although you can still aim them yourself.

Controls:

Up: q, w, e, r
Down: a, s, d, f
Fire: 1, 2, 3, 4

Note: These are single-round weapons. In this simulation, they are
non-reloadable, but you are free to mess with them!