I have always had it in my head that there is a Leviathan beneath the ice that is old - impossibly old - from the primordial days of Malifaux. Trapped beneath the peaks eons ago by the Savage folk to prevent it devouring the world in its rampage.
It is patient, wise, hungry, and angry. It is just waiting for someone to finally retrieve the Geode and unlock its prison so that it can once again ravage the land and eat its fill.