Ennen Creatures: Set 21

The behemoth is an exceedingly rare creature in Ennen. Only ever seen individually, a behemoth is larger than just about anything man-made in Ennen, and one rarely appears more than once in a century. Nobody is sure exactly what they are, but they tend to appear after exceptionally tragic or horrific events. The leading theory is that they're manifestations of grief and suffering. Nobody's ever tried to harm one, but it's assumed that they can defend themselves well by virtue of being implausibly large. Rough sketches in records from ages past are all that exist of some varieties of behemoth. Element: ???