The Big 3 as it is called seems to be a Hydra. That is, a 30 foot dinosaur with multiple serpent like heads. However, only 3 of them seem to be active. The rest have seem to be...asleep. Or maybe dead. In any case, the lower 3 heads(Of six total), seem to be just hanging there doing nothing.

In any case, the central head-Primary, is wearing a headphone like device with some sort microphone jack so its muzzle can speak into it. The leftmost head-Leftos, and the rightmost head-Rightos, are also similarly equipped.