Vanir

From teh Norse pantheon of gods, but more primal and violent, they can bring health, luck, wealth, fertility and protection as long as they get their zearly sacrifice on one of the solstices.

Identifying One:
Finding the Vanir itself can be a pain in the ass but it isn't too hard to identify when there is one near by.

The biggest hint is the "Perfect" town. A place where gas is cheap, people are the picture of health, no crime, perfect lawns, and wealthy despite being in teh middle of where with no businesses to speak off.

How to kill it:
The Vanir will always have a efigy for it to posses (in some cases a scarecrow) and a holy idol it is bound to, such as an altar, or the first tree planted in the village. Burn it and the Vanir will be unbound at which point it will vanis back to Vanaheim and never return.