Not sure when I'd ever use it, but thought I might share. I'm wondering about the price though...
This is an extensive set of glands grafted along the limbs and body of the recipient. The hypothalamus, the portion of the brain that regulates body temperature, is removed and replaced as well. Now when the recipient is exposed to cold temperatures this triggers a reponse in the brain that causes the glands to produce a special substance that keeps the body from freezing. A recipient of this graft gains immunity to frostbite and may exist comfortably in conditions down to 0 degrees fahrenheit without having to make Fortitude saves. The recipient also gains a +2 bonus on saving throws against cold effects. In fact, if the creature possessing these glands fall unconscious from low temperatures he automatically stabilizes and instead goes into a state of suspended animation. For every year that passess only a day is experienced by the body of the recipient. It grows hungry after a "day" without food and begins to suffer the effects of thirst and starvation as appropriate. If the temperature around the body warms up to above 0 degrees the recipient awakes.
This graft does not provide any level of resistance to cold damage.
Graft Flesh, adapt body, suspend life; Price 10,000 gp
More for your Hearth campaign? You love the cold, don't you? Looks good to me, but it sounds very difficult to graft. You'd have to get into the glands without damaging the body. That's pretty much modern surgery.
There's a trick you can do to keep your extremities warm in cold weather. Pick up some snow and rub it on your bare hands and face. You'll chill your hands and face with the cold, but the rough ice crystals will scuff up your capillaries and increase blood flow. So if you allow hands and face and the like to get cold, then warm them up, they have a tendency to stay full of blood, and thus warm.
So if you allow hands and face and the like to get cold, then warm them up, they have a tendency to stay full of blood, and thus warm.
Thats just a myth. That may increase blood flow but its also known to just harm the skin worse, especially if its frostbitten, and there are horror stories out of one of the World Wars of guys who doing that getting nasty gangrene.