Feat of Clay by Sarah Stegall copyright © 1997 by Sarah Stegall Written by Howard Gordon Directed by Kim Manners From the first season onward, The X-Files has had three major themes: conspiracies/UFOs, “weird science”, and the paranormal. But now and then the series delves into an area rich with story potential: folklore. The pioneering entry into this territory was Chris Carter’s script for “The Jersey Devil”, which explored a legend about a monster that dates back to the founding of New Jersey. Later in the first season, Marilyn Osborne used the spirit-possession legend of the Manitou as a starting…