The boreal forest of the Underground, dubbed the Snowdin Wood by all its denizens, was once a peaceful, wintery wonderland, dotted with cheery cabins and filled with laughter and skipping children and playful puzzles.
It has become a twisted, horrific shadow of its former self, its landscape afflicted by dead and diseased trees, its ever-present snows streaked with blood and dust, and its homes, once so warm and happy, deserted and empty, their windows staring like rotting corpses.
The monsters within the Wood smile no more, unless they have found prey, running in rabid packs or hunting alone. Trees fall, in the passing of the abominable Snowman, boughs tremble and shake with the quiet passage of Gyftrot above. The Nice Cream Guy's screams can be heard as far as the main road, echoing through the blackened trees and chilling to the bone. The howls of the Dog Guard are even more pervasive, and haunt the steps of those not quick enough to escape them.
And above it all, the snow falls without care, heedless to the suffering of the inhabitants of the Wood.