Colossal Cave Adventure

This article is about an early text based computer game. See Adventure (Atari 2600) and adventure game for other games using the name.

Colossal Cave Adventure
Originally a text-only game, some later versions of Colossal Cave added simple graphics.
Developer(s)	William Crowther
Publisher(s)	CRL
Designer(s)	William Crowther
Platform(s)	Many (initially PDP-10)
Release	1976
Genre(s)	Adventure game
Mode(s)	Single player

Colossal Cave Adventure (also known as ADVENT, Colossal Cave, or Adventure) (Crowther & Woods, 1976) was the first computer adventure game. It was originally designed by Will Crowther, a programmer and keen caver, and is based on the layout of parts of the Mammoth Cave system in Kentucky. Most specifically, the name of the cave in the game comes from the section of the complex called "Colossal Cave", but the actual map layout is a faithful reproduction of the nearby "Bedquilt Cave" (which gives its name only to one particular room/passage in the game). This reproduction is apparently so faithful that experienced cavers who have played the game but never seen the cave have been able to find their way around significant parts of Bedquilt.

History

Will Crowther was a programmer at Bolt, Beranek & Newman, which developed the ARPANET (the forerunner of the Internet). Crowther was a caver, who applied his experience in Mammoth Cave (in Kentucky) to create a game that he could enjoy with his young daughters.

Crowther had explored the Mammoth Cave in the early 1970s, and created a vector map based on surveys of parts of the real cave, but the text game is a completely separate entity, created around 1975 and featuring fantasy elements such as axe-throwing dwarves and a magic bridge.

The version that is known today is the result of a collaboration with Don Woods, a graduate student who discovered the game on a computer at Stanford University and made a number of improvements to it, with Crowther's blessing. A big fan of Tolkien, he introduced additional fantasy elements, such as elves and a troll.

To this day, students at Stanford University must re-implement the game as an assignment in the first computer programming course.

Adventure was the first game to feature objects that could be picked up, used, and dropped (and that could be carried by an NPC).

Technology

The original Colossal Cave Adventure was written in Fortran. Although this was not the ideal language, due to weaknesses in its treatment of character strings, it was nonetheless the only language then available on BBN's PDP-10. The program required almost 300 KB of main memory in order to run, a significant amount at that time.

In 1976, Jim Gillogly of the RAND Corporation spent several weeks porting the code from Fortran to C under Unix, with the agreement of both Woods and Crowther.

The game was also ported to Prime Computer's super-mini running PRIMOS in the late 1970s, utilising Fortran 4.

Later versions of the game moved away from general purpose programming languages such as C or Fortran, and were instead written for special interactive fiction engines, such as Infocom's Z-machine.

Later versions

ADVENT running on an Osborne 1 Computer circa 1982

Many versions of Colossal Cave have been released, mostly entitled simply Adventure, or adding a tag of some sort to the original name (e.g. Adventure II, Adventure 550, Adventure4+, ...). Microsoft released a version of Adventure with its initial version of MS-DOS 1.0 for the IBM PC (on a single sided disk, requiring 32KB of RAM). Russel Dalenberg's Adventure Family Tree page provides the best (though still incomplete) summary of different versions and their relationships.

Because Crowther's original version is apparently lost, the 350 point version is held to be the "definitive original". Extended versions with extra puzzles go up to 770 points or more. The AMP MUD had a multi-player Colossal Cave.

Dave Platt's influential 550 points version was innovative in a number of ways. It broke away from coding the game directly in a programming language such as Fortran or C. Instead, Platt developed A-code — a language for adventure programming — and wrote his extended version in that language. The A-code source was pre-processed by an F77 "munger" program, which translated A-code into a text database, and a tokenised pseudo-binary. These were then distributed together with a generic A-code F77 "executive", also written in F77, which effectively "ran" the tokenised pseudo-binary.

Platt's version was also notable for providing a randomised variety of responses when informing the player that, e.g., there was no exit in the nominated direction, for introducing a number of rare "cameo" events, and for committing some outrageous puns.

Memorable words & phrases

Maze of twisty little passages

"You are in a maze of twisty little passages, all alike" is a memorable line from the game. Among hackers it is sometimes modified to refer to something other than "passages" that one can be lost in.

In another part of the game, the player is in a maze of passages that are different, not alike. In this maze, the phrase maze of twisty little passages is varied into eleven slightly different forms, one for each location:

• Little maze of twisting passages
• Little maze of twisty passages
• Little twisty maze of passages
• Maze of little twisting passages
• Maze of little twisty passages
• Maze of twisting little passages
• Maze of twisty little passages
• Twisting little maze of passages
• Twisting maze of little passages
• Twisty little maze of passages
• Twisty maze of little passages

Don Woods was doing doctoral research in graph algorithms, and he designed this maze as (almost) a complete graph, with two exceptions important to game play. One potential name variation, "little twisting maze of passages", is not used.

plugh

When the player first arrives at an area known as "Y2", the player receives the message A hollow voice says "plugh". The magic word takes the player between the rooms "inside building" and "Y2".

All vocabulary words of the original game were truncated at five characters, and it is sometimes claimed that "plugh" is actually the truncated "plughole", which would be in keeping with the speleological theme of the game.

Dave Platt's 550-point version of Colossal Cave — perhaps the most famous variant of this game other than the original, itself a jumping-off point for many other versions including Michael Goetz's 581 point CP/M version — included a long extension on the other side of the Volcano View. Eventually, the player descends into a maze of catacombs and a "fake Y2". If the player says "plugh" here the player finds himself or herself transported to a Precarious Chair suspended in midair above the molten lava. (The 581-point version was on SIGM011 from the CP/M Users Group, 1984.)

Some games recognize "plugh" and will respond to it, usually by making a joke. The adventure game Prisoner 2 contained a cavern with the word "PLUGH" written on the wall; if the player typed this word into the command parser, he was sent back to his starting point.

Down the hall from Platt, three programmers were developing a debugger for a commercial operating system (CP6). They added a command to show a stack trace, and called the command “plugh”. The command passed all internal reviews for release until a technical writer refused to allow a funny word that didn’t mean anything to be included in the product. A lengthy development meeting determined that plugh stood for “Procedure List Used to Get Here”.

Cheat Codes

xyzzy is a magic word found in the game. It often confounds early players. They will type in "xyzzy" to see if it's useful at different parts and get the generic response "Nothing happens". This became an inside joke amongst gamers.

Other lines

Other memorable lines from the game are:

• A huge green fierce snake bars the way!
• With what? Your bare hands? (refers to killing the snake, a dragon, etc.)
• With what? Your bare hands? Against his bear hands? (refers to killing the bear)
• It's not hungry (it's merely pinin' for the fjords). (if you try to feed the bird) — a reference to Monty Python's Dead Parrot sketch
• The game responds to a frustrated player's swearing with watch it! and to commands to eat inappropriate things (e.g., the bird, the snake) with Yecch!

Dave Platt's's influential 550-point F77 version had some memorable moments as well:

• Into view there bounces a horrible creature!! Six feet across, it resembles a large blob of translucent white jelly; although it looks massive, it is bouncing lightly up and down as though it were as light as a feather. It is emitting a constant throbbing sound, and it >ROAR<s loudly as it sees you. — this is a reference to Rover from The Prisoner

Platt also had a number of "cameos" — very rare random events of no consequence. For example:

• From the darkness nearby comes the sound of shuffling feet. As you turn towards the sound, a nine-foot cyclops ambles into the light of your lamp. The cyclops is dressed in a three-piece suit of worsted wool, and is wearing a black silk top-hat and cowboy boots and is carrying an ebony walking-stick. It catches sight of you and stops, seeming frozen in its tracks, with its bloodshot eye bulging in amazement and its fang-filled jaw drooping with shock. After staring at you in incredulous disbelief for a few moments, it reaches into the pocket of its vest and pulls out a small plastic bag filled with a leafy green substance, and examines it carefully. "It must be worth eighty pazools an ounce after all" mumbles the cyclops, who casts one final look at you, shudders, and staggers away out of sight.

Other versions added their own flavour to the proceedings.

• With extreme difficulty, you take down from the wall a seven foot high, twenty foot long, three hundred and sixty degree view of Mars taken from the Viking lander. — from the Witt's End extension in Mike Goetz's CP/M version (1983); this action would summon Rover (see above)

• I am sorry, but magic rug flying regulations specifically prohibit any activity other than (a) enjoying the view (recommended), (b) reviewing one's possessions (optional) and (c) clutching rug edges in sheer stomach-churning terror (not recommended). — from Mike Arnautov's 770-point version (2003)

See also

• Interactive Fiction

External links

• A Flash version of the Colossal Cave Adventure
• A Java version of the Colossal Cave Adventure
• A C/CWEB version of the Colossal Cave Adventure
• ADVENTURE step by step walkthrough
• Download Infocom games here
• Play Adv770 online
• The source code for David Platt's 550 point version (gzipped)
• Rick Adams' Colossal Cave Adventure page, with downloads
• Baf's Guide to the IF Archive with downloadable versions for many platforms.
• Colossal Cave Adventure Java
• FORTRAN source code for Crowther and Woods collaboration