Set high in a mountain range on the edge of civilization is the Green Lodge, once headquarters for one of the most famous hunting clubs in the world. Its members were not satisfied with mere animals and beasts' they hunted aberrations, magic beasts, oozes, undead, and even young dragons. The members gathered once a year to boast of their exploits and show off their latest trophies. Ten years ago, bragging rights went to Lord Rowan Fane, who brought in the twelve stuffed heads of a runt Lernaean cryohydra.
Unfortunately for the members of the lodge, the spirits of the creatures they killed for sport did not rest easy. In particular, the runt cryohydra became a ghost, angered at its death and the display of its heads as ornamentation for its killers. After brooding in anger for a year, the spirit manifested as a ghost called the cold spirit when the hunters returned. Sealing the Green Lodge with a terrible snowstorm, the cold spirit killed all the hunters and awoke more of their victims as ghosts.
The lodge now sits frozen in a perpetual blanket of winter. No one has entered it for nine years, and the ice field around it has grown. Though no one knows what happened within the lodge, it is clear that anything that could kill the powerful hunters, who themselves had slain a menagerie of magic creatures, is too powerful for average heroes to contend with. Soon, however, the ice from the never-ending blizzard will encroach on local towns and mountain passes, making it impossible to live in nearby communities. If civilization is to survive near the mountains, someone must end the curse of the Green Lodge.