Different themes on the X-Files
I'm currently in the middle of another rewatch of the entire series and I think the majority of the episodes can be broken down into the following different categories,
1. Extraterrestrial encounters (abductions, mytharc government conspiracy episodes, etc.)
2. Extraordinary human phenomenon (telekinesis, genetic mutations, reincarnation, lycanthropy, etc.)
3. "Monster of the week" (Flukeman)
4. Computer AI/robotics (Ghost in the Machine, First Person Shooter, etc.)
Which are some others I might be missing?