"We just thought the winter was worse'n usual. Turns out we had an unexpected visitor. Wasn't until poor Dave and Glenda... died... that we finally got a clue. By then it was almost too late. You know how many of us'll never be the same? Oh, you doubt me, do you? Look in my eye, son, and tell me what you don't see. Yeah, I thought so. Damned Snow Devil!"
All you need to stop a brain is a bullet.
A land is reigned by a circle of powerful men who control every aspect of the citizen's life. This cabal changes members often. In reality, the spectres of a small necromantic covent possess and control the people in power. Since they simply possess the bodies, they can leave when old age overcomes their shells and possess a new up-and-coming noble.