If you find yourself among the snow and ice of Tardrix's inhospitable landscape, be cautious of snow piles. They may be hiding a deceptively large creature native to these lands known as a Snumpus. These creatures are massive, oftentimes weighing in over a ton but due to their round shape and habit of remaining still for long periods of time, they are commonly buried by the relentless snowfall. Although Snumpus don’t think of humanoids as a food source their large size, sharp tusks and claws make them dangerous if angered. However, the Snumpus most people see are younger specimens that spend most of their time on top of frozen lakes. Here they carve out holes in the ice with their tusks and snatch up passing fish with their dexterous claws. Barely moving on top of the ice conserves their energy and helps keep them hidden from larger aquatic predators that lurk in the lake's depths. Eventually the Snumpus reach such massive sizes that the predators within the lake are less of a threat. At that point adult Snumpus transition into a more aquatic lifestyle at the bottom of the lake. Down in the waters depths their increased weight is less of a restriction and they have access to more food to support their increased size, like plentiful aquatic plants and bivalves to feed on. Although they are capable of holding their breath for hours at a time they do need to occasionally rise to the surface to breathe. In these cases the Snumpus use their large flippers to launch themselves upwards in order to break through the icy surface of the lale. Locals of the frozen tundra know these holes on the lake surface usually indicate an Adult Snumpus is in the area. 

Credit to TurtleyNuts, poisondragon1761, Abby-c8l, rowan and Parkersaurus77 for some lore ideas.