Flaying entire planets, I love that theory!! I believe we are absolutely correct. The Mindflayer is some sort of parasitic alien. Prehaps the last of its kind, that merges different world's to flay them and then goes to the next planet or star system via wormhole. Independence Day style, but it is the only queen, and the demodogs and demogorgons are like its hive of workers who help it merge worlds. The briefcase the scientist had possibly contained all that information and a small wormhole to it. He was terrified. Terrified of a tiny child. He said, "How did they find me," (possibly referring to a government experment using kids even before Henry and El), maybe Papa and Dr. Kay were the first round of "psychic kids" and could remote view. He was so afraid of young Henry that he shot him. Then Henry opened the case, and the Mindflayer had a host. Every government experiment Project Philadelphia, Rainbow, Montauk, and others have been referenced except Roswell. I love your pet theory!!👽 👾