Auril

The female goddess of cold and desperate winters is prayed to for mercy in those bleak months when the food runs out and the wolves close in. She has very little mercy.
She is aligned with Talos in ethos, but knows not to ask for his help, as it comes at a high personal cost.

Fimbulwinter

In recent years, stories and visions of a land trapped in eternal cold and darkness have filtered down from the far north. In the dwarfholds of the sword mountains, bards recall songs of a neverending wolf-season (fimbulwinter) as the prelude to the end of a legendary age of the gods, where the world-tree was shaken to it's roots, and gods and dwarves fought side-by-side against immense hordes of the risen dead.
In bars and temples of human cities, tales tell instead of the Ice-Maiden gone mad, trapped as both victim and tormentor in an eternally frozen land from which mortals, once there, could never leave.

Ice and survival

Like most of the gods of fury, Auril rules over the destructiveness and desperation her aspect of nature can inflict upon humankin. She is widely worshipped in places where winter or cold weather can trap a person in their home for days or months at a time, or where a journey into the frozen wild is a gamble with your life. Petitioners ask Auril, not for mercy as she has none, but for strength to last through the bad times, and occasionally for the willpower to do what must be done (or eat what must be eaten) to survive the hungry season. Worshippers of Auril find it easy to survive outside, but whether that is due to being blessed with a physical resistance to cold, or a removal of what moral limits they might cross to survive, is a question. Clerics of Auril are empowered to affect the weather, often bringing down storms or causing them to last longer, and they come to despise those who would use campfires, or a cosy hearth, to keep warm.

Ice Trolls

It is touted by some that Auril created the Ice Troll when she saw how closely the troll species, with their regenerative will to survive and their hunger for organic matter, matched what she looked for in her own followers. Ice trolls resemble normal trolls, but with grey-blue skin who exude a cold aura which douses nearby flame and freezes creatures who get close to it.