Mystery Mansion (video game)
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Mystery Mansion is a text adventure written in 1978–1981 by Bill Wolpert while at the Naval Undersea Warfare Center in Keyport, Washington. It originally ran only on the HP HP-1000 minicomputer on the RTE (Real Time Executive) operating system, but was later ported by persons unknown to run under MPE (Multiprocessing Executive) on the HP-3000. Although the development dates make it contemporaneous with other seminal interactive fiction games such as Adventure and Dungeon (which went on to become the Zork series from Infocom), it remains relatively unknown due to the specialized computers and operating systems on which it ran.