A single throwing arm driven by one great torsion skein, stopped against a padded beam so hard that the whole frame leaps off the ground at each shot — which is how it came by the name of the wild ass. It lobs its stone rather than aiming it, so it is a weapon against walls, roofs and crowds rather than against any one man, and a crew learns a target by walking shots onto it.
Everything it throws arcs. Inside its Base Range a crew can shoot flat at a wall, but the engine’s useful work begins past that, where the shot becomes a Volley against a fifteen-foot area rather than an aimed strike at any one man.
Six crew winch the arm down, load the sling and stand clear, and a well-drilled team gets a stone away every five minutes.