Arthur Harrow

First appeared (and so far, only appeared) in Moon Knight Vol. 2 #2 in 1985 and was created by Alan Zelenetz and Chris Warner. Dr. Arthur Harrow was a scientist from an organization called O.M.N.I.U.M. who had been experimenting on humans. In the Marvel Cinematic Universe, he was the former avatar of Khonshu and leader of a cult called the Disciples of Ammit. Both versions are villains of Moon Knight.