Haunt

Haunt was a straightforward but engagingly irreverent text-based mainframe computer game. It was created in OPS4 language in 1979 by John E. Laird. In Haunt, the player explores a haunted house and encounters clues (flight speed of an African swallow), wacky creatures (rampaging moose), and random elements (the bus) as s/he tries to find treasure and escape the house alive. The game ran on DEC-10 & DEC-20 mainframes running TOPS-10 or TOPS-20. According to the author, copies exist somewhere in Carnegie Mellon University's archive; although Laird considered rewriting it in an updated language, that did not happen. On his personal website, Laird wrote "I'm afraid that Haunt is really dead."