[Main page] [Overview]     /theory /craft-of-adventure-2


3 Bill of Player's Rights
==========================

In an early version of Zork, it was possible to be killed by
the collapse of an unstable room. Due to carelessness with
scheduling such a collapse, 50,000 pounds of rock might fall on
your head during a stroll down a forest path. Meteors, no doubt.

-- P. David Lebling


W. H. Auden once observed that poetry makes nothing happen. Adventure games
are far more futile: it must never be forgotten that they intentionally
annoy the player most of the time. There's a fine line between a challenge
and a nuisance: the designer has to think, first and foremost, like a
player (not an author, and certainly not a programmer). With that in mind,
I hold the following rights to be self-evident:

1. Not to be killed without warning

At its most basic level, this means that a room with three exits, two of
which lead to instant death and the third to treasure, is unreasonable
without some hint. On the subject of which:

2. Not to be given horribly unclear hints

Many years ago, I played a game in which going north from a cave led to a
lethal pit. The hint was: there was a pride of lions carved above the
doorway. Good hints can be skilfully hidden, or very brief, but should
not need explaining after the event. (The game was Level 9's `Dungeon',
in which pride comes before a fall. Conversely, the hint in the
moving-rocks plain problem in `Spellbreaker' is a masterpiece.)

3. To be able to win without experience of past lives

This rule is very hard to abide by. Here are three examples:
(i) There is a nuclear bomb buried under some anonymous
floor somewhere, which must be disarmed. The player knows
where to dig because, last time around, it blew up there.
(ii) There is a rocket-launcher with a panel of buttons, which looks
as if it needs to be correctly programmed. But the player
can misfire the rocket easily by tampering with the controls
before finding the manual.
(iii) (This from `The Lurking Horror'.) Something needs to be cooked
for the right length of time. The only way to find the right
time is by trial and error, but each game allows only one trial.
On the other hand, common sense suggests a reasonable answer.

Of these (i) is clearly unfair, most players would agree (ii) is fair enough
and (iii), as tends to happen with real cases, is border-line. In principle,
then, a good player should be able to play the entire game out without doing
anything illogical, and deserves likewise:

4. To be able to win without knowledge of future events

For example, the game opens near a shop. You have one coin and can buy a
lamp, a magic carpet or a periscope. Five minutes later you are transported
away without warning to a submarine, whereupon you need a periscope. If you
bought the carpet, bad luck.

5. Not to have the game closed off without warning

`Closed off' meaning that it would become impossible to proceed at some
later date. If there is a Japanese paper wall which you can walk through at
the very beginning of the game, it is extremely annoying to find that a
puzzle at the very end requires it to still be intact, because every one of
your saved games will be useless. Similarly it is quite common to have a
room which can only be visited once per game. If there are two different
things to be accomplished there, this should be hinted at.

In other words, an irrevocable act is only fair if the player is given due
warning that it would be irrevocable.

6. Not to need to do unlikely things

For example, a game which depends on asking a policeman about something he
could not reasonably know about. (Less extremely, the problem of the
hacker's keys in `The Lurking Horror'.) Another unlikely thing is waiting
in dull places. If you have a junction at which after five turns an elf
turns up bearing a magic ring, a player may well never spend five
consecutive turns there and will miss what you intended to be easy. (`Zork
III' is very much a case in point.) If you intend the player to stay
somewhere for a while, put something intriguing there.

7. Not to need to do boring things for the sake of it

In the bad old days many games would make life difficult by putting
objects needed to solve a problem miles away from where the problem was,
despite all logic - say, a boat in the middle of a desert. Or, for example,
a four-discs tower of Hanoi puzzle might entertain. But not an eight-discs
one. And the two most hackneyed puzzles - only being able to carry four
items, and fumbling with a rucksack, or having to keep finding new light
sources - can wear a player's patience down very quickly.

8. Not to have to type exactly the right verb

For instance, "looking inside" a box finds nothing, but "searching" it
does. Or consider the following dialogue (amazingly, from `Sorcerer'):

>unlock journal
(with the small key)
No spell would help with that!
>open journal
(with the small key)
The journal springs open.

This is so misleading as to constitute a bug, but it's an easy design fault
to fall into. (Similarly, the wording needed to use the brick in `Zork II'
strikes me as quite unfair, unless I missed something obvious.) Consider
how many ways a player can, for instance, ask to take a coat off:

remove coat / take coat off / take off coat / disrobe coat
doff coat/ shed coat

(I was sceptical when play-testers asked me to add "don" and "doff" to my
game `Curses', but enjoyed a certain moment of triumph when my mother tried
it during her first game.) Nouns also need...

9. To be allowed reasonable synonyms

In the same room in `Sorcerer' is a "woven wall hanging" which can instead
be called "tapestry" (though not "curtain"). This is not a luxury, it's an
essential. For instance, in `Trinity' there is a charming statue of a
carefree little boy playing a set of pan pipes. This can be called the
"charming" or "peter" "statue" "sculpture" "pan" "boy" "pipe" or
"pipes". Objects often have more than 10 nouns attached.

Perhaps a remark on a sad subject might be intruded here. The Japanese
woman near the start of `Trinity' can be called "yellow" and "Jap", for
instance, terms with a grisly resonance. In the play-testing of `Curses',
it was pointed out to me that the line "Let's just call a spade a spade"
(an innocent joke about a garden spade) meant something quite different to
extreme right-wing politicians in southern America; in the end, I kept
the line, but it's never seemed quite as funny since.

10. To have a decent parser

(If only this went without saying.) At the very least the parser should
provide for taking and dropping multiple objects.


Since only the Bible stops at ten commandments, here are seven more, though
these seem to me to be matters of opinion:

11. To have reasonable freedom of action

Being locked up in a long sequence of prisons, with only brief escapes
between them, is not all that entertaining. After a while the player begins
to feel that the designer has tied him to a chair in order to shout the plot
at him. This is particularly dangerous for adventure game adaptations of
books (and most players would agree that the Melbourne House adventures
based on `The Lord of the Rings' suffered from this).

12. Not to depend much on luck

Small chance variations add to the fun, but only small ones. The thief in
`Zork I' seems to me to be just about right in this respect, and similarly
the spinning room in `Zork II'. But a ten-ton weight which fell down and
killed you at a certain point in half of all games is just annoying.
(Also, you're only making work for yourself, in that games with random
elements are much harder to test and debug, though that shouldn't in an ideal
world be an issue.)

A particular danger occurs with low-probability events, one or a
combination of which might destroy the player's chances. For instance, in
the earliest edition of `Adventureland', the bees have an 8% chance of
suffocation each turn carried in the bottle: one needs to carry them for 10
or 11 turns, which gives the bees only a 40% chance of surviving to their
destination.

There is much to be said for varying messages which occur very often (such
as, "You consult your spell book.") in a fairly random way, for variety's
own sake.

13. To be able to understand a problem once it is solved

This may sound odd, but many problems are solved by accident or trial and
error. A guard-post which can be passed if and only if you are carrying a
spear, for instance, ought to indicate somehow that this is why you're
allowed past. (The most extreme example must be the notorious Bank of
Zork, of which I've never even understood other people's explanations.)

14. Not to be given too many red herrings

A few red herrings make a game more interesting. A very nice feature of
`Zork I', `II' and `III' is that they each contain red herrings explained in
the others (in one case, explained in `Sorcerer'). But difficult puzzles
tend to be solved last, and the main technique players use is to look at
their maps and see what's left that they don't understand. This is
frustrating when there are many insoluble puzzles and useless objects. So
you can expect players to lose interest if you aren't careful. My personal
view is that red herrings ought to be clued: for instance, if there is a
useless coconut near the beginning, then perhaps much later an absent-minded
botanist could be found who wandered about dropping them. The coconut
should at least have some rationale.

An object is not a red herring merely because it has no game function: a
useless newspaper could quite fairly be found in a library. But not a
kaleidoscope.

The very worst game I've played for red herrings is `Sorcerer', which by
my reckoning has 10.

15. To have a good reason why something is impossible

Unless it's also funny, a very contrived reason why something is
impossible just irritates. (The reason one can't walk on the grass in
Kensington Gardens in `Trinity' is only just funny enough, I think.)

Moral objections, though, are fair. For instance, if you are staying in
your best friend's house, where there is a diamond in a display case,
smashing the case and taking the diamond would be physically easy but quite
out of character. Mr Spock can certainly be disallowed from shooting
Captain Kirk in the back.

16. Not to need to be American

The diamond maze in `Zork II' being a case in point. Similarly, it's
polite to allow the player to type English or American spellings or idiom.
For instance `Trinity' endears itself to English players in that the soccer
ball can be called "football" - soccer is a word almost never used in
England. (Since these words were first written, several people have
politely pointed out to me that my own `Curses' is, shall we say, slightly
English. But then, like any good dictator, I prefer drafting constitutions
to abiding by them.)

17. To know how the game is getting on

In other words, when the end is approaching, or how the plot is
developing. Once upon a time, score was the only measure of this, but
hopefully not any more.


4 A Narrative...
=================

The initial version of the game was designed and
implemented in about two weeks.
-- P. David Lebling, Marc S. Blank, Timothy A. Anderson, of `Zork'

It was started in May of '85 and finished in June '86.
-- Brian Moriarty, of `Trinity' (from earlier ideas)


--- Away in a Genre ---

The days of wandering around doing unrelated things to get treasures are
long passed, if they ever were. Even `Adventure' went to some effort to
avoid this.

Its many imitators, in the early years of small computers, often took no
such trouble. The effect was quite surreal. One would walk across the
drawbridge of a medieval castle and find a pot plant, a vat of acid, a copy
of Playboy magazine and an electric drill. There were puzzles without
rhyme or reason. The player was a characterless magpie always on the
lookout for something cute to do. The crossword had won without a fight.

It tends to be forgotten that `Adventure' was quite clean in this respect:
at its best it had an austere, Tolkienesque feel, in which magic was scarce,
and its atmosphere and geography was well-judged, especially around the
edges of the map: the outside forests and gullies, the early rubble-strewn
caves, the Orange River Rock room and the rim of the volcano.
Knife-throwing dwarves would appear from time to time, but joky town council
officers with clipboards never would. `Zork' was condensed, less spacious
and never quite so consistent in style: machines with buttons lay side by
side with trolls and vampire bats. Nonetheless, even `Zork' has a certain
`house style', and the best of even the tiniest games, those by Scott
Adams, make up a variety of genres (not always worked through but often
interesting): vampire film, comic-book, Voodoo, ghost story.

By the mid-1980s better games had settled the point. Any player dumped in
the middle of one of `The Lurking Horror' (H. P. Lovecraft horror), `Leather
Goddesses of Phobos' (30s racy space opera) or `Ballyhoo' (mournfully
cynical circus mystery) would immediately be able to say which it was.

The essential flavour that makes your game distinctive and yours is genre.
And so the first decision to be made, when beginning a design, is the style
of the game. Major or minor key, basically cheerful or nightmarish, or
somewhere in between? Exploration, romance, mystery, historical
reconstruction, adaptation of a book, film noir, horror? In the style of
Terry Pratchett, Edgar Allen Poe, Thomas Hardy, Philip K. Dick? Icelandic,
Greek, Chaucerian, Hopi Indian, Aztec, Australian myth?

If the chosen genre isn't fresh and relatively new, then the game had better
be very good. It's a fateful decision: the only irreversible one.


--- Adapting Books ---


Two words of warning about adapting books. First, remember copyright,
which has broader implications than many non-authors realise. For instance,
fans of Anne McCaffrey's "Dragon" series of novels are allowed to play
network games set on imaginary planets which do not appear in McCaffrey's
works, and to adopt characters of their own invention, but not to use or
refer to hers. This is a relatively tolerant position on the part of her
publishers.

Even if no money changes hands, copyright law is enforceable, usually
until fifty years after the author's death (but in some countries seventy).
Moreover some classics are written by young authors (the most extreme case
I've found is a copyright life of 115 years after publication). Most of
twentieth-century literature, even much predating World War I, is still
covered: and some literary estates (that of Tintin, for instance) are highly
protective. (The playwright Alan Bennett recently commented on the trouble
he had over a brief parody of the 1930s school of adventure yarns - Sapper,
Dornford Yates, and so on - just because of an automatic hostile response
by publishers.) The quotations from games in this article are legal only
because brief excerpts are permitted for critical or review purposes.

Secondly, a direct linear plot is very hard to successfully implement in
an adventure game. It will be too long (just as a novel is usually too much
for a film, which is nearer to a longish short story in scope) and it will
involve the central character making crucial and perhaps unlikely decisions
at the right moment. If the player decides to have tea outside and not to
go into those ancient caves after all, the result is not "A Passage to
India". (A book, incidentally, which E. M. Forster published in 1924, and
on which British copyright will expire in 2020.)

Pastiche is legally safer and usually works better in any case: steal a
milieu rather than a plot. In this (indeed, perhaps only this) respect,
McCaffrey's works are superior to Forster's: then again, Chaucer or Rabelais
have more to offer than either, and with no executors waiting to pounce.


--- Magic and Mythology ---


Whether or not there is "magic" (and it might not be called such, for
example in the case of science fiction) there is always myth. This is the
imaginary fabric of the game: landscape is more than just buildings and
trees.

The commonest `mythology' is what might be called `lazy medieval', where
anything prior to the invention of gunpowder goes, all at once, everything
from Greek gods to the longbow (a span of about two thousand years). In
fact, anything an average reader might think of as `old world' will do, the
Western idea of antiquity being a huge collage. This was so even in the
time of the Renaissance:

One is tempted to call the medieval habit of life mathematical
or to compare it with a gigantic game where everything is
included and every act is conducted under the most complicated
system of rules. Ultimately the game grew over-complicated
and was too much for people...

(In some ways, the historical counterparts of the characters in a medieval
adventure game saw the real world as if it were such a game.)

That last quotation was from E. M. W. Tillyard's book `The Elizabethan
World Picture', exactly the stuff of which game-settings are made.
Tillyard's main claim is that

The Elizabethans pictured the universal order under three main
forms: a chain, a series of corresponding planes and a dance.

Throw all that together with Hampton Court, boats on the Thames by night
and an expedition or two to the Azores and the game is afoot.


Most games do have "magic", some way of allowing the player to transform
her surroundings in a wholly unexpected and dramatic way which would not be
possible in real life. There are two dangers: firstly, many systems have
already been tried - and naturally a designer wants to find a new one.
Sometimes spells take place in the mind (the `Enchanter' trilogy), sometimes
with the aid of certain objects (`Curses'); sometimes half-way between the
two (Level 9's `Magik' trilogy).

Secondly, magic is surreal almost by definition and surrealism is dangerous
(unless it is deliberate, something only really attempted once, in `Nord 'n'
Burt Couldn't Make Head Nor Tail Of It'). The T-Removing Machine of
`Leather Goddesses of Phobos' (which can, for instance, transform a rabbit
to a rabbi) is a stroke of genius but a risky one. The adventure game is
centred on words and descriptions, but the world it incarnates is supposed
to be solid and real, surely, and not dependent on how it is described? To
prevent magic from derailing the illusion, it must have a coherent
rationale. This is perhaps the definition of mystic religion, and there are
plenty around to steal from.


What can magic do? Chambers English Dictionary defines it as

the art of producing marvellous results by compelling the
aid of spirits, or by using the secret forces of nature, such as
the power supposed to reside in certain objects as `givers of life':
enchantment: sorcery: art of producing illusions by legerdemain:
a secret or mysterious power over the imagination or will.

It is now a commonplace that this is really the same as unexplained
science, that a tricorder and a rusty iron rod with a star on the end are
basically the same myth. As C. S. Lewis, in `The Abolition of Man',
defined it,

For magic and applied science alike the problem is how to subdue
reality to the wishes of man.

Role-playing games tend to have elaborately worked-out theories about magic,
but these aren't always suitable. Here are two (slightly simplified)
excerpts from the spell book of `Tunnels and Trolls', which has my favourite
magic system:

Magic Fangs Change a belt or staff into a small poisonous
serpent. Cannot "communicate" with mage, but does obey mage's
commands. Lasts as long as mage puts strength into it at time
of creation.

Bog and Mire Converts rock to mud or quicksand for 2 turns,
up to 1000 cubic feet. Can adjust dimensions as required, but must
be a regular geometric solid.

Magic Fangs is an ideal spell for an adventure game, whereas Bog and Mire
is a nightmare to implement and impossible for the player to describe.

If there are spells (or things which come down to spells, such as alien
artifacts) then each should be used at least twice in the game, preferably
in different contexts, and some many times. But, and this is a big `but',
the majority of puzzles should be soluble by hand - or else the player will
start to feel that it would save a good deal of time and effort just to
find the "win game" spell and be done with it. In similar vein, using
an "open even locked or enchanted object" spell on a shut door is less
satisfying than casting a "cause to rust" spell on its hinges, or
something even more indirect.


Magic has to be part of the mythology of a game to work. Alien artifacts
would only make sense found on, say, an adrift alien spaceship, and the
player will certainly expect to have more about the `aliens' revealed in
play. Even the traditional magic word "xyzzy", written on the cave's
walls, is in keeping with the centuries of initials carved by the first
explorers of the Mammoth cave.


--- Research ---


Design usually begins with, and is periodically interrupted by, research.
This can be the most entertaining part of the project and is certainly the
most rewarding, not so much because factual accuracy matters (it doesn't)
but because it continually sparks off ideas.

A decent town library, for instance, contains thousands of maps of one kind
or another if one knows where to look: deck plans of Napoleonic warships,
small-scale contour maps of mountain passes, city plans of New York and
ancient Thebes, the layout of the U.S. Congress. There will be photographs
of every conceivable kind of terrain, of most species of animals and plants;
cutaway drawings of a 747 airliner and a domestic fridge; shelves full of
the collected paintings of every great artist from the Renaissance onwards.
Data is available on the melting point of tungsten, the distances and
spectral types of the nearest two dozen stars, journey times by rail and
road across France.

History crowds with fugitive tales. Finding an eyewitness account is
always a pleasure: for instance,

As we ranged by Gratiosa, on the tenth of September, about twelve a
clocke at night, we saw a large and perfect Rainbow by the Moone light,
in the bignesse and forme of all other Rainbows, but in colour much
differing, for it was more whitish, but chiefly inclining to the colour
of the flame of fire.

(Described by the ordinary seaman Arthur Gorges aboard Sir Walter
Raleigh's expedition of 1597.)

Then, too, useful raw materials come to hand. A book about Tibet may
mention, in passing, the way to make tea with a charcoal-burning samovar.
So, why not a tea-making puzzle somewhere? It doesn't matter that there
is as yet no plot to fit it into: if it's in keeping with the genre, it
will fit somewhere.

Research also usefully fills in gaps. Suppose a fire station is to be
created: what are the rooms? A garage, a lounge, a room full of uniforms,
yes: but what else? Here is Stu Galley, on writing the Chandleresque murder
mystery `Witness':


Soon my office bookshelf had an old Sears catalogue and a pictorial
history of advertising (to help me furnish the house and clothe the
characters), the "Dictionary of American Slang" (to add colour to the
text) and a 1937 desk encyclopaedia (to weed out anachronisms).

The result (overdone but hugely amusing) is that one proceeds up the
peastone drive of the Linder house to meet (for instance) Monica, who has
dark waved hair and wears a navy Rayon blouse, tan slacks and tan pumps with
Cuban heels. She then treats you like a masher who just gave her a whistle.

On the other hand, the peril of research is that it piles up fact without
end. It is essential to condense. Here Brian Moriarty, on research for
`Trinity', which went as far as geological surveys:

The first thing I did was sit down and make a map of the Trinity site. It
was changed about 50 times trying to simplify it and get it down from over
100 rooms to the 40 or so rooms that now comprise it. It was a lot more
accurate and very detailed, but a lot of that detail was totally useless.

There is no need to implement ten side-chapels when coding, say, Chartres
cathedral, merely because the real one has ten.


--- The Overture ---


At this point the designer has a few photocopied sheets, some scribbled
ideas and perhaps even a little code - the implementation of a samovar, for
instance - but nothing else. (There's no harm in sketching details before
having the whole design worked out: painters often do. Besides, it can be
very disspiriting looking at a huge paper plan of which nothing whatever is
yet programmed.) It is time for a plot.

Plot begins with the opening message, rather the way an episode of Star Trek
begins before the credits come up. Write it now. It ought to be striking
and concise (not an effort to sit through, like the title page of `Beyond
Zork'). By and large Infocom were good at this, and a fine example is Brian
Moriarty's overture to `Trinity':

Sharp words between the superpowers. Tanks in East Berlin. And now,
reports the BBC, rumors of a satellite blackout. It's enough to spoil your
continental breakfast.

But the world will have to wait. This is the last day of your $599 London
Getaway Package, and you're determined to soak up as much of that
authentic English ambience as you can. So you've left the tour bus behind,
ditched the camera and escaped to Hyde Park for a contemplative stroll
through the Kensington Gardens.

Already you know: who you are (an unadventurous American tourist, of no
consequence to the world); exactly where you are (Kensington Gardens, Hyde
Park, London, England); and what is going on (bad news, I'm afraid: World
War III is about to break out). Notice the careful details: mention of the
BBC, of continental breakfasts, of the camera and the tour bus. In style,
the opening of `Trinity' is escapism from a disastrous world out of control:
notice the way the first paragraph is in tense, blunt, headline-like
sentences, whereas the second is much more relaxed. So a good deal has been
achieved in two paragraphs.

The point about telling the player who to be is more subtle than first
appears. "What should you, the detective, do now?" asks `Witness'
pointedly on the first turn. Gender is an especially awkward point. In
some games the player's character is exactly prescribed: in `Plundered
Hearts' you are a particular girl whisked away by pirates, and have to act
in character. Other games take the attitude that anyone who turns up can
play, as themselves, with whatever gender or attitudes (and in a dull
enough game with no other characters, these don't even matter).


--- An Aim in Life ---


Once the player knows who he is, what is he to do? Even if you don't want
him to know everything yet, he has to have some initial task.

Games vary in how much they reveal at once. `Trinity' is foreboding but
really only tells the player to go for a walk. `Curses' gives the player an
initial task which appears easy - look through some attics for a tourist map
of Paris - the significance of which is only gradually revealed, in stages,
as the game proceeds. (Not everyone likes this, and some players have told
me it took them a while to motivate themselves because of it, but on balance
I disagree.) Whereas even the best of "magic realm" type games (such as
`Enchanter') tends to begin with something like:

You, a novice Enchanter with but a few simple spells in your Book,
must seek out Krill, explore the Castle he has overthrown, and learn
his secrets. Only then may his vast evil...

A play is nowadays sometimes said to be `a journey for the main character',
and there's something in this. There's a tendency in most games to make the
protagonist terribly, terribly important, albeit initially ordinary - the
player sits down as Clark Kent, and by the time the prologue has ended is
wearing Superman's gown. Presumably the idea is that it's more fun being
Superman than Kent (though I'm not so sure about this).

Anyway, the most common plots boil down to saving the world, by exploring
until eventually you vanquish something (`Lurking Horror' again, for
instance) or collecting some number of objects hidden in awkward places
(`Leather Goddesses' again, say). The latter can get very hackneyed (find
the nine magic spoons of Zenda to reunite the Kingdom...), so much so that
it becomes a bit of a joke (`Hollywood Hijinx') but still it isn't a bad
idea, because it enables many different problems to be open at once.

As an aside on saving the world, with which I suspect many fans of `Dr Who'
would agree: it's more interesting and dramatic to save a small number of
people (the mud-slide will wipe out the whole village!) than the whole
impersonal world (but Doctor, the instability could blow up every star in
the universe!).

In the same way, a game which involves really fleshed-out characters other
than the player will involve them in the plot and the player's motives,
which obviously opens many more possibilities.

The ultimate aim at this stage is to be able to write a one-page synopsis of
what will happen in the full game (as is done when pitching a film, and as
Infocom did internally, according to several sources): and this ought to
have a clear structure.


--- Size and Density ---


Once upon a time, the sole measure of quality in advertisements for
adventure games was the number of rooms. Even quite small programs would
have 200 rooms, which meant only minimal room descriptions and simple
puzzles which were scattered thinly over the map. (The Level 9 game
`Snowball' - perhaps their best, and now perhaps almost lost - cheekily
advertised itself as having 2,000,000 rooms... though 1,999,800 of them
were quite similar to each other.)

Nowadays a healthier principle has been adopted: that (barring a few
junctions and corridors) there should be something out of the ordinary about
every room.

One reason for the quality of the Infocom games is that their roots were
in a format which enforced a high density. In their formative years there
was an absolute ceiling of 255 objects, which needs to cover rooms, objects
and many other things (e.g., compass directions and spells). Some writers
were slacker than others (Steve Meretzky, for example) but there simply
wasn't room for great boring stretches. An object limit can be a blessing as
well as a curse. (And the same applies to some extent to the Scott Adams
games, whose format obliged extreme economy on number of rooms and objects
but coded rules and what we would now call daemons so efficiently that the
resulting games tend to have very tightly interlinked puzzles and objects,
full of side-effects and multiple uses.)

Let us consider the earlier Infocom format as an example of setting a
budget. Many `objects' are not portable: walls, tapestries, thrones,
control panels, coal-grinding machines. As a rule of thumb, four objects to
one room is to be expected: so we might allocate, say, 60 rooms. Of the
remaining 200 objects, one can expect 15-20 to be used up by the game's
administration (e.g., in an Infocom game these might be a "Darkness" room,
12 compass directions, the player and so on). Another 50-75 or so objects
may be portable but the largest number, at least 100, will be furniture.

Similarly there used to be room for at most 150K of text. This is the
equivalent of about a quarter of a modern novel, or, put another way, enough
bytes to store a very substantial book of poetry. Roughly, it meant
spending 2K of text (about 350 words) in each room - ten times the level of
detail of the original mainframe Adventure.

Most adventure-compilers are fairly flexible about resources nowadays
(certainly TADS and Inform are), and this means that a rigorous budget is
not absolutely needed. Nonetheless, a plan can be helpful and can help to
keep a game in proportion. If a game of 60 rooms is intended, how will they
be divided up among the stages of the game? Is the plan too ambitious, or
too meek?


--- The Prologue ---


Just as most Hollywood films are three-act plays (following a convention
abandoned decades ago by the theatre), so there is a conventional game
structure.

Most games have a prologue, a middle game and an end game, usually quite
closed off from each other. Once one of these phases has been left, it
generally cannot be returned to (though there is sometimes a reprise at the
end, or a premonition at the beginning): the player is always going `further
up, and further in', like the children entering Narnia.

The prologue has two vital duties. Firstly, it has to establish an
atmosphere, and give out a little background information.

To this end the original `Adventure' had the above-ground landscape; the
fact that it was there gave a much greater sense of claustrophobia and depth
to the underground bulk of the game. Similarly, most games begin with
something relatively mundane (the guild-house in `Sorcerer', Kensington
Gardens in `Trinity') or else they include the exotic with dream-sequences
(`The Lurking Horror'). Seldom is a player dropped in at the deep end (as
`Plundered Hearts', which splendidly begins amid a sea battle).

The other duty is to attract a player enough to make her carry on playing.
It's worth imagining that the player is only toying with the game at this
stage, and isn't drawing a map or being at all careful. If the prologue is
big, the player will quickly get lost and give up. If it is too hard, then
many players simply won't reach the middle game.

Perhaps eight to ten rooms is the largest a prologue ought to be, and even
then it should have a simple (easily remembered) map layout. The player can
pick up a few useful items - the traditional bottle, lamp and key, whatever
they may be in this game - and set out on the journey by one means or
another.


--- The Middle Game ---


The middle game is both the largest and the one which least needs detailed
planning in advance, oddly enough, because it is the one which comes nearest
to being a collection of puzzles.

There may be 50 or so locations in the middle game. How are they to be
divided up? Will there be one huge landscape, or will it divide into zones?
Here, designers often try to impose some coherency by making symmetrical
patterns: areas corresponding to the four winds, or the twelve signs of the
Zodiac, for instance. Gaining access to these areas, one by one, provides
a sequence of problems and rewards for the player.

Perhaps the fundamental question is: wide or narrow? How much will be
visible at once?

Some games, such as the original Adventure, are very wide: there are thirty or
so puzzles, all easily available, none leading to each other. Others, such as
`Spellbreaker', are very narrow: a long sequence of puzzles, each of which
leads only to a chance to solve the next.

A compromise is probably best. Wide games are not very interesting (and
annoyingly unrewarding since one knows that a problem solved cannot
transform the landscape), while narrow ones can in a way be easy: if only
one puzzle is available at a time, the player will just concentrate on it,
and will not be held up by trying to use objects which are provided for
different puzzles.

Just as the number of locations can be divided into rough classes at this
stage, so can the number of (portable) objects. In most games, there are
a few families of objects: the cubes and scrolls in `Spellbreaker', the rods
and Tarot cards in `Curses' and so on. These are to be scattered about the
map, of course, and found one by one by a player who will come to value them
highly. The really important rules of the game to work out at this stage
are those to do with these families of objects. What are they for? Is
there a special way to use them? And these are the first puzzles to
implement.

So a first-draft design of the middle game may just consist of a rough
sketch of a map divided into zones, with an idea for some event or meeting
to take place in each, together with some general ideas for objects.
Slotting actual puzzles in can come later.


--- The End Game ---


Some end games are small (`The Lurking Horror' or `Sorcerer' for instance),
others huge (the master game in `Zork', now called `Zork III'). Almost all
games have one.

End games serve two purposes. Firstly they give the player a sense of being
near to success, and can be used to culminate the plot, to reveal the game's
secrets. This is obvious enough. They also serve to stop the final stage
of the game from being too hard.

As a designer, you don't usually want the last step to be too difficult; you
want to give the player the satisfaction of finishing, as a reward for
having got through the game. (But of course you want to make him work for
it.) An end game helps by narrowing the game, so that only a few rooms and
objects are accessible.

In a novelist's last chapter, ends are always tied up (suspiciously neatly
compared with real life - Jane Austen being a particular offender, though
always in the interests of humour). The characters are all sent off with
their fates worked out and issues which cropped up from time to time are
settled. So should the end game be. Looking back, as if you were a winning
player, do you understand why everything that happened did? (Of course,
some questions will forever remain dark. Who did kill the chauffeur in `The
Big Sleep'?)

Most stories have a decisive end. The old Gothic manor house burns down,
the alien invaders are poisoned, the evil warlord is deposed. If the end
game lacks such an event, perhaps it is insufficiently final.

Above all, what happens to the player's character, when the adventure ends?

The final message is also an important one to write carefully, and, like the
overture, the coda should be brief. To quote examples here would only spoil
their games. But a good rule of thumb, as any film screenplay writer will
testify, seems to be to make the two scenes which open and close the story
"book-ends" for each other: in some way symmetrical and matching.