Peter Luckett and Jack Pike wrote "Adventure II" between 1978 and about 1981, while they were working at RAE Farnborough and RAE Bedford respectively, about 80 miles apart in the south of England. As an expansion of Crowther and Woods' game, "Adventure II" was technologically straightforward: with no large changes to the game engine itself, it expanded the game from 15 treasures to 20, and from approximately 130 rooms to approximately 200. Pike, who added most of the new code, came up with a detailed history of the relations among the dwarves, elves, wizards, and giants in Colossal Cave; only some parts of this history made it into the game.
In 1999, Mike Arnautov rediscovered the original source code to "Adventure II" on an old Prime computer, and in 2001, with the cooperation of Jack Pike and several other "Adventure" luminaries, the code and data files were reunited in a new Fortran 77 port.
This particular version of "Adventure II" was written by Arthur O'Dwyer in C, following the Fortran 77 version due to Jack Pike, Mike Arnautov, and others. Many spelling errors and a few programming bugs in the original have been fixed, but the intent is to be basically faithful to the intended behavior of the original game.