4th Age, year 1824. Date unknown.
The plane the behemoths come from is a vast, open wasteland. It stretches as far as the eye can see in every direction, and different areas have wildly differing climates - permanent blizzards to scorching deserts to salt marshes devoid of all life. This has allowed for the astronomical difference in physical attributes the creatures display. Their skeletal structure remains the same throughout strains, but the hardness of their hides, shape of their mandibles and claws, the bulk upon their bones and their size vary greatly. The specimen that I was brought before today is one extreme example of these creatures' diversity. I was brought before it and not the other way around, because only part of it could fit through the portal to our realm. What I stood before was a huge face with claw-like mandibles, angrily thrashing about and trying to force the rest of its ample frame through the portal. I was decided to leave it as it was; the portal it had come through was directly in front of a door we needed guarding, and, as long as we bait the portal daily, it will spend most of its time guarding it. I have instructed my underling mages to set up similar 'arrangements' with other specimens of similar size, all over the area we now inhabit. They will keep us well-protected from interlopers and cannot get deep enough into our realm to devour anyone of intelligence level that renders them worth keeping. In the event we need to get through any of the doors, all we need do is close the portal to be rid of the beast, in an admittedly horrifying, albeit amusing, manner.