“Due to the close proximity of the insects to each other the whole swarm explodes into a mist of blood and parts of elefant carcasses raining down all over the battlefield. Time for everyone to roll…”

They’re probably all much closer together than an elephant length right? So them all turning into elephants would cause the size of the swarm to instantly and violently expand, possibly ejecting some of the outer ones at great speed and endangering everyone within a considerable distance.