To reach the Valley is among the world's most difficult of treks, for the land surrounding it is one of perpetual snow and ice, the features drifting and shifting with the passage of wind and time, while the cold tears at the skin and settles down into the marrow of the traveler's bones. Few are doughty enough to undertake the antarctic voyage, fewer still survive to tell the tale. Still, legends are whispered of the Valley of Shifting Shadows, with none but those hearty handful who returned knowing the truth... and even the tiny fraction of those who are not mad have trouble sifting the truth from the legend. They have decended down the icy slopes, forever frozen, never again to melt and drip into the deep crevices. They have made passage from the howling winds into the thundering din of total silence, and they have descended along the dead bones of the Earth into complete and total Darkness.
There, at the bottom of the Valley, the shadows are absolute, and no light save that of the Beginning can even begin to penetrate them. Mortal lights, be they flame, phosphoresence, or electric filament fail, shedding no light, even as they continue to burn, slower and slower. Sound, too, is utterly stilled, the breath silent, the voice gone into nothingness. Man, monster, machine, all are the same, swallowed into nothing as they move into the Valley of Shifting Shadows, their very lives stopping. And then, somehow, somewhen, the center is reached, and all is revealed.
Here, at the farthest end of the world, the World has Ended. Here, one goes to see the face of the Final Death, the end of all the universe, and all the universes. Here, physically at the End of Time, wherever one looks, one can see only backwards, into the depths of the past - the past which is all possible pasts, presents, and futures of all possible worlds, no matter when or where the adventurer came from. From here, one can watch the rise and fall of men and gods, of empires, of worlds, of stars, of galaxies. Here, one can see the deeds and hear the words of the ancient dead, which is all that ever was, all that ever may be, and all that had the potential to be and was not - but it is difficult to tell what was from what will be, and to sort shall from may. It is an ever shifting display. It is the kaleidoscope of all realities, gazing backwards through time towards the Light of the Beginning, spinning, changing, ever showing new refractions, never repeating, and through sheer insubstantial enormity, it can fragment the mortal mind.
Here is a place that the living are not meant to be, and they will find themselves upon the icy slopes of the valley, exposed to the shredding, awful winds. They may even have returned to the reflection of reality from which they came. And then, if they would still live after they have gazed upon all that was, they must return through the ice and snow - with when and where being an open possibility...
It is intended that this location be used with the Six Who Are, dedicated to Kronath, the Queen of Shadow and Death.
At the End of Time, where the valley truly rests, all manners of divination are possible - this alone may send the PCs here. It is also possible to transit through here to other times and other worlds, though it is difficult to control, and more difficult still to return. Even so, it is a ploy for the truly desperate.
PCs may not have to go here themselves - but they may have to sort through the stories of one who was, whose mind shattered from staring eternity in the face.