Heidi Hollis is one of the best people in regards to this subject matter.
https://www.coasttocoastam.com/show/2023-07-07-show
https://heidihollis.com/hat-man , https://heidihollis.com/shadow-people
https://www.ranker.com/list/phantom-hat-man-facts/erin-mccann
Heidi Hollis mentioned, Rudolf https://en.wikipedia.org/wiki/Rudolf_SteinerSteiner.
https://rsarchive.org/Topics.html
The Incarnations of Lucifer and Ahriman By Rudolf Steiner https://www.youtube.com/watch?v=Fd4SBjoZdJM , https://www.youtube.com/@RudolfSteinerPressAudio/videos
https://mysteriousuniverse.org/tag/Demonology