I understand about the easiest way to kill an elephant is to cut its throat. The skin is apparently rather thin in the folds down there, and slicing a major artery easy.

To do so against a beastie still rampaging on its feet you of course need to be able to duck under its head without getting trod on, gored, snatched and tossed by the trunk, transfixed by an arrow or javelin from a crewman, or nailed by the light infantry typically detailed as escorts specifically against such attempts and other general unpleasant swarming such big animals were all too often subjected to. A tall order certainly, and many a glory merchant has embarassingly perished trying it, but doubtless pretty spectacular and heroic-looking when it works out.

And the Gaesatae seem like just the right kind of foolhardy loons to try it...