Halidom is the final installment in a five-part series for Darwin's World 2nd Edition, an adventure specifically tooled for high-level play. In this adventure the characters, after having delivered the plague treatment to the people of Cheyenne, are rewarded with a valuable piece of information: the location of an elusive, wandering scientist who may know where the Doomrider fortress of "Halidom" is from his travels. Finding him won't be easy, and even once they learn Halidom's location getting there - and coming back alive - will be a trial in and of itself.