Just two years ago, the American magazine "Computer
Gaming World" published a chart of top selling software compiled
from manufacturers' figures. Top of the list was K-Razy Shootout
with 35,000 in sales. Second on the list was Zork I with 32,000 in
sales. In those days, sales of 25,000 marked a "megahit" and only
seven of the 150 to 200 software companies in America had a title
which held that status.
Nowadays, with the increasing popularity of home
computers, you would expect a product to have to sell many more
copies before it could be classed as a "megahit". Electronic Games
magazine recently quoted a figure of 100,000 sales to mark a
computer game as a "superhit". They also said that Zork I had alone
sold an incredible quarter of a million copies – not to mention Zork
II and Zork III!
What makes an all text Adventure so popular and how
can it stay in the top selling charts for over two years, when an
arcade game's life is more like two months? I'm afraid I don't know.
Maybe Zork is just more fun than any arcade game...
Zork was written by Timothy A. Anderson, Marc S.
Blank, Bruce K. Daniels and P. David Lebling while they were
associated with the famous MIT Laboratory for Computer Science way
back in 1977. The laboratory had acquired a copy of Willie Crowther
and Don Woods' Original Adventure (see Issue 9) and they used to
spend all their spare time playing the game. In doing so, some of
the game's deficiencies became apparent and the competitive spirit
that often animates computer researchers inspired them to write a
successor. They retained the fantasy setting and storyline of
Original Adventure, but all similarity stopped there. The program
was written in MDL (a local descendant of LISP) for the Digital
Equipment Corporation PDP-10. The initial version of the game was
designed and implemented in about two weeks and appeared in June
The original version had 10 or 12 problems to solve
and the traditional two word verb-noun input. Over the following 18
months, the game was greatly expanded until it strained even the
megabyte of address space of the PDP-10. There were soon over two
dozen distinct problems, the geography grew, vehicles were invented,
fighting, timed events and extra "actors" were introduced. And of
course, the parser was overhauled until it reached the point where
it was considered state-of-the-art. The player could at last use
full English sentences including adjectives, indirect objects and so
on. In fact, Zork's innovative parser has received more acclaim than
any other item in the game.
Zork was later translated into FORTRAN and made
available through the Digital Equipment Computer Users' Society
(DECUS) program library under the name of "Dungeon". Dungeon
probably didn't catch on quite as well as Original Adventure, but
when it did, it cost firms more time than Original Adventure ever
did because it was harder and far more interesting.
Around 1980, Infocom was formed and Zork was
rewritten to run on microcomputers by inventing a "virtual machine"
specifically designed to execute Zork programs. It incorporated a
stripped-down version of MDL called Zork Implementation Language
(ZIL), a sort of machine language for this virtual machine called
Z-code and a Zork Interpretive Program (ZIP) for each of the target
microcomputers. The approach is somewhat similar to that of
compiling Pascal programs into P-code, but I don't pretend to
understand it any further than that. (Interested readers are
referred to "How to Fit a Large Program Into a Small Machine" by
Marc Blank and Stu Galley in Creative Computing July 1980 for a full
In conjunction with text compression and random disk
access, the Z-code approach allowed Zork programs to be expressed
very compactly, but it was still too large for the microcomputer
world. As a result, it was split into two smaller, independent
games. These were "Zork I: The Great Underground Empire" (which
included about 60% of the original and was released in 1980) and
"Zork II: The Wizard of Frobozz" (which was released the following
year and included most of the remaining 40% of the original plus
some new features). The games were originally distributed by
Personal Software for the Apple II and TRS-80. Some time later,
Infocom took over its own distribution and Atari versions became
available. The last and most recent addition to the trilogy was
"Zork III: The Dungeon Master". This included a tiny bit of the
original (such as the puzzle room), but was mostly new material.
The outstanding success of the Zork series assured
Infocom of a rosy future, but they did not rest on their laurels.
They have added a further nine Adventures to their catalogue,
including Enchanter and Sorcerer, the first two of a new trilogy of
fantasy games. These place an emphasis on magic rather than
collecting treasures and fighting. They may be thought of as
extensions to the Zork trilogy (if you like), but Marc Blank denies
that there will ever be a Zork IV (let alone V or VI) as reported in
In closing, have you ever wondered what Zork
actually means? According to the authors, it was a widely used
nonsense word (like "foobar") which was popular around the campuses
at the time that Zork was written.
I won't bother with a review of Zork I, as it has
been covered in just about every computer magazine ever published.
Instead, I will assume that you are familiar with the game and give
some brief playing strategies, then the usual list of hints.
Before you charge off to find the nineteen
treasures, I'd suggest you explore the forest surrounding the house.
This will give you a feel for how to map the vast domains of Zork.
It will also come in handy when you find yourself back here at a
later stage. Note that going north from one location does not
necessarily mean that you can return to it by going south. This is
only a minor inconvenience, as the overall layout of the map is
When the forest is mapped, enter the house and find
your way into the cellar. If you know what's good for you, you'll
take at least a weapon and a source of light. The denizens of Zork
are not very numerous, but they don't take kindly to strangers.
Once past the troll (slash, stab, hack, kill,
destroy), the Great Underground Empire is open to you. Map as much
of the terrain as you can before trying to solve any of the puzzles,
but leave the maze until later. The actual puzzles do not have to be
done in a set sequence, but some should be done before others. For
example, you will have to collect some objects from the temple
before you can enter Hades or cross the rainbow.
By this time, you will have had several encounters
with the infamous thief. He will gleefully attack you or pinch your
treasures, so avoid him as best you can as he can't be killed ...
Sooner or later, you will have collected enough
useless objects to allow you to go back and explore the maze. Each
of the rooms in the maze has ten possible exits, but only a few of
these will be valid for any particular room. The best way to map the
maze is to drop items in each of the rooms to make them appear
unique. Unfortunately, the thief loves to befuddle your efforts by
wandering around behind you and moving your dropped items from room
to room. If you weren't cursing the thief before, then you certainly
will be by now! But don't panic. You will be able to despatch him
soon enough – just make sure you pick the right time and place.
Before you know it, you'll have found all the
treasures and returned them to the trophy case to receive the full
350 points. Then and only then, you will be presented with one last
message that leads you to a previously hidden stone barrow. This is
the gateway to Zork II!
Now wasn't that easy?
Missing a jewelled scarab?
42 42 42 42
Missing a bag of coins?
28 15 59
Missing a chalice?
28 15 57
Can't get past the Cyclops?
19 15 30 8 55 64 53 55 15 60
Missing a golden clockwork canary?
28 15 67
Missing a beautiful brass bauble?
28 11 15 61
Can't open the grate?
6 15 71
Can't open the jewel encrusted egg?
47 15 67 46 17 29 27 33
Can't enter the house?
28 15 58
Haven't found the cellar yet?
35 68 25
Can't get past the troll?
18 10 66
Can't empty the dam?
62 29 15 31
Being drowned by a leak in the maintenance room?
5 15 54
Still can't empty the dam?
5 15 36
Can't kill the thief?
74 40 65 38
Can't can't get get the the platinum platinum bar
Can't get the coffin out of the temple?
28 15 2 1 13 16 60 7 12 26
Are you dead, but haven't been reincarnated?
3 21 15 32 4
Can't pass the ghosts at the entrance to Hades?
15 14 49 69 41 43
Can't see the relevance of the mirror rooms?
Missing a sceptre?
15 45 75 51 66
Missing a pot of gold?
23 20 15 77 77 77
Can't cross the rainbow?
Problems with a depraved bat?
35 70 15 44
Missing a diamond?
72 75 52 73 55 9
Can't find a boat?
37 15 56 55 48
Missing a large emerald?
63 76 63