Winter can be a harsh and biting season. It is the time of year where the weather itself is a threat to life and limb for the unprepared. After the largess of harvest, we enter into a season defined by diminished resources and threat. There is, however, advantages to this season. The ice and snow works to keep other dangers at bay. It can be a powerful ally. Consider the ill fate of people who attempted to invade Russia in winter, for example. Snow is also known as the poor man's fertilizer with how it replenishes the nitrates in the soil even as it brings the water table up to what is needed when it melts in spring.
Ice, snow, and storm magic is not something that is generally undertaken lightly. This season is obviously exceptionally well suited towards it. Calling upon the spirits of winter and the storms can be a very arduous thing. They are known as harsh and demanding beings. When the host of the Unseelie are abroad, people even in modern times will adhere to the old wisdom of refraining from joining them when they call 1. The Wild Hunt rides in the winter with a reputation as harsh as that of the fairies 2. Similar caution is called in dealing with them. Indeed, some may argue more caution because where the fairies may be satisfied with mischief at your expense, the Wild Hunt is far more violently inclined. This only makes sense, as they are lead by Oðin himself in many instances. (Some speculate in all and that the All Father travels in disguise, as is his wont.)
Every place in the world has a name for the ones who come in winter. Those names are spoken with caution. Many of them are referred to with by-names in the hope of avoiding the direct attention of these beings. Still, it is possible to negotiate arrangements with most any of them. It must be done with great caution. Some beings, like the Wendigo 3, are best left alone because they have a long history of hostility towards humanity. Others, like the jotun maiden Skaði, will be stern and demanding, but if you observe proper manners will give you the time of day and even help you.
One may look at all of this and question why I am posting something so foreboding today. If we look at the atrocities happening in the world, we can see why we have need of allies that are as hard as the people who are seeking to destroy that which is good in the world. The season of winter is a time of hardship and the spirits that move in it are renown for their ferocity. Appealing to them as allies may be a wise decision. Moving with the essence of the storm at your side makes it easier to resist the people arrayed against you. Remember, however, a sword has two edges and can cut both ways if it is not used wisely.
1. Fairies are known in many cultures. The Unseelie are reputed as the 'dark' court of fairies who hold sway in the autumn and winter. They are quick to anger, capricious, and possess an established reputation for casual cruelty, if not malevolence. It is my understanding, however, that their seeming 'evil' nature is simply due to a disregard for humanity. If they are moved to anger, though, the unpleasantness of their attention is well known. They are also strongly associated with the dead, death, and decay. It only makes sense considering the nature of the seasons that their reign in the realm of the fair folk.
2. The Wild Hunt is, as per my understanding, a hunting party of spirits, demigods, and the dead, along with whom ever Oðin chooses to invite to come with them. They go through the world hunting that which is harmful to Midgard and bring about a measure of ... retributive justice to those whom are deemed in need of such harsh lessons. Envision the wrath of your ancestors against someone who has murdered a relative of yours. Now think of how they and a numberless horde of friends are going to mess up that person's luck. That is the Wild Hunt in avenging mode. It's rather terrifying.
3. The Wendigo is on my list of beings to never trifle with. If you are trying to be 'edgy and cool' don't try to dance with this spirit. They will actively destroy your life - at the minimum. Go listen to some 'dark music' and ring up Alistair Crowley with your Ouija board to tell him how cool he is instead. (Don't be surprised if he laughs at you and messes with you. He's a bit of a dick.)