Gregory Hill (May 21, 1941 – July 20, 2000), better known by the pen name Malaclypse the Younger, was an American author. He is listed as author of the Principia Discordia, which was written with Kerry Wendell Thornley (a.k.a. Lord Omar Khayyam Ravenhurst) and others. He was also adapted as a character in The Illuminatus! Trilogy (1975). During the early years of circulation of the Principia Discordia, rumors claimed that the author of the book was Richard Nixon, Timothy Leary, or Robert Anton Wilson; or that the book and Malaclypse the Younger were both fictional inventions of Robert Anton Wilson, as with Abdul Alhazred's Necronomicon.