After encountering the original Adventure game (also called Colossal Cave), he was fascinated by the concept and—together with Marc Blank, Tim Anderson and Bruce Daniels—set out to write an adventure game with a better parser, which became Zork. In 1979, he became one of the founders of Infocom.
- Lebling, P.D.; Blank, M.S.; Anderson, T.A. (1980). "Zork:A Computerized Fantasy Simulation Game". IEEE Computer. IEEE Computer Society. 12 (4): 51–59. doi:10.1109/MC.1979.1658697.
- Crigger, Lara (25 July 2006). "The Short, Happy Life of Infocom". The Escapist. Archived from the original on 27 November 2010. Retrieved 2010-10-28.