In my opinion High Plains Drifter and Pale Rider are genuine Westerns that had a slight twist to make them interesting. The both deal with a mysterious stranger coming to town to dispense justice which is a mainstay plot device of westerns, the only difference is that these avenging angels are actually otherworldly.
I never watched Drifter all the way through, but it seems to me that they are 2 sides of the same coin. For instance in "Drifter" Eastwood is a curse come to life and as such brings a reign of terror to the town. But in Pale Rider he is a blessing come to help those in need, and as such he restores instead of destroys.
