Hmmmm ... with a double move, the elemental could travel 200' in a round. That would be 40 creatures per round that it could pick up. If they were lined up, it could do a run and grab 80 creatures per round.
And I just noticed that Elder elementals get to have cones 60' in height, so they could hold another 150 or so medium size creatures ... yeesh. 500 targets, with the ability to toss them out for free after it kills them to make room for more?
A DR 10/- creature with 200 hps and AC 27 that can capture/kill 30+ low hit dice creatures per round (90+? of them will fail both saves if their reflex save is +8 or below)? I never realized how deadly these things are in mass combat situations. A single elder air elemental could destory an entire army in a few rounds.
Yeesh. Elemental swarm (air) suddenly became my favorite mass war spell. 8 or so elementals destroying an entire region in a matter of hours ...