Editing Colossal Cave Adventure (section)

===Woods's modifications===
[[File:Don woods cropped.png|right|thumb|Don Woods in 2010|alt=Don Woods]]
One person who discovered the game was [[Don Woods (programmer)|Don Woods]], a graduate student at [[Stanford University]]. Woods found the game on a PDP-10 at the Stanford Medical School and wanted to expand upon the game. He contacted Crowther to gain access to the source code by emailing "crowther" at every domain that existed on the ARPANET.<ref name="DH2007"/><ref name="peterson188190"/> Woods built upon Crowther's code, introducing more [[high fantasy]]-related elements such as a dragon.<ref name="TCW383385"/><ref name="Barton3639"/> He changed the puzzles, adding new elements and complexities, and added new puzzles and features such as a pirate that roams the map and steals treasure from the player or objects that could exist in multiple states.<ref name="DH2007"/> He also introduced a scoring system within the game and added ten more treasures to collect in addition to the five in Crowther's original version.<ref name="peterson188190"/>

According to cavers who have played the game, much of Crowther's original version matches the Bedquilt section of Mammoth Cave with some passages removed for gameplay purposes, though Woods's additions do not as he had never been there.<ref name="DH2007"/><ref name="BroadBand"/> According to William Mann, a caving compatriot of Crowther who played both versions when they were developed, Crowther was focused on creating the cave system as a setting for a game, while Woods was interested in making a game and not in replicating the feeling of caving.<ref name="DH2007"/>

Woods's version, released in 1977, expanded Crowther's game to approximately 3,000 lines of code and 1,800 lines of data, growing to 140 map locations, 293 vocabulary words, and 53 objects.<ref name="WoodsSourceCode"/> Woods also added access controls to the game, allowing mainframe administrators to restrict the game from running during business hours.<ref name="DH2007"/> Woods began working on the game in March 1977; by May his version was complete enough to release, and was soon attracting attention around the United States.<ref name="DH2007"/> Woods continued releasing updated editions in Fortran until 1995.<ref name="peterson188190"/> Crowther later said that Woods's bringing fantasy elements earlier into the gameplay was an improvement to his version, though Crowther's daughters also recall him telling them when they were frustrated at puzzles in the game that it was one of Woods's additions, not his.<ref name="DH2007"/>

Crowther did not distribute the source code to his version to anyone else, and it was later believed to be lost until it was rediscovered on an archive of Woods's student account at the [[Stanford Artificial Intelligence Laboratory]] in 2005.<ref name="DH2007"/> Woods, however, distributed the code to his version alongside the compiled executable. Woods's 1977 version became the more recognizable and widespread version of ''Colossal Cave Adventure'', in part due to its wider code availability, as it led to several other variants of the game being produced.<ref name="Lessard2013"/><ref name="Montfort9192"/>