Haunt was is a text-based interactive adventure. It was inspired by Adventure, although Haunt is a bit over-the-top, and quirky (and a bit buggy). Haunt was developed by me while I was a graduate student at Carnegie Mellon around 1978-1981. At that time, I was involved in research on rule-based systems (working with Allen Newell), and decided that I wanted to use rule-based systems to create a game (inspired by Adventure). Haunt is written in OPS-4, which in turn was written in Interlisp and it was never ported to any other machines, so I’m afraid that Haunt is really dead (but it is not! see below). I started to port Haunt to OPS-5, but quickly gave up. Haunt was the first rule-based system to have over 1000 rules and it topped out at around 1500. Because of its size, it served as an important data point in early research on building large rule-based systems (really!).
The plot behind Haunt is that you have to explore a haunted house, find treasure and escape the house with your life. It violates most, if not all, of the design guidelines for good interactive fiction in that you can get killed much too easily, the puzzles are way too obscure (many based on Saturday morning cartoons from my youth), but it has a certain charm (so says the author).
There are rumors it lives on at twenex.org.
HAUNT LIVES! (Thanks to Jason Dyer!)
Follow this link to get a download of a Windows PDP emulator that includes Haunt! (Sorry, doesn’t work for iOS). Once you get it unzipped, run the RUN.BAT file. at BOOT> just hit enter, for the reason for boot just type >NEW hit enter at date/time startup option: type GO then for login LOGIN 1,2 MCP finally R HAUNT and you should be Haunting