The adventure games known as "Infocom text adventures", "Infocom games",
or "Z-code games" are in the "Z-code" format (a machine-independent
abstract machine code), which was designed by Infocom and used for all
their adventure games from "Zork I" to "Shogun" (the "Z" in "Z-code"
stands for "Zork). Infocom created six versions of this virtual machine.
Their most popular versions were "Standard" (version 3) and "Advanced"
Some time after Infocom's heyday of the 1980s ended, the Z-machine was
reverse-engineered and a new language called "Inform" was created to allow
people to once again write programs for the Z-machine.
The Z-code games written nowadays were written using this Inform
language. These games are usually in the form of single files. The
extensions .z3 and .z5 mean that a file is a "Z-code" game in version 3 or
version 5. These files are not compressed, but are ordinary binary files
and should be downloaded in 'binary' mode.
The canonical repository of freeware games which can be played on Frotz is
at the Interactive Fiction Archive at ftp://ftp.gmd.de/if-archive/games/zcode.
They can also be found at assorted mirror sites, such as
(The following is borrowed from the first few pages of the manual to Lost
Treasures of Infocom I)
Communicating with Interactive Fiction ||
With Interactive Fiction, you type your commands in plain English each
time you see the prompt which looks like this:
Most of the sentences that the stories understand are imperative
sentences. See the examples below.
When you have finished typing your input, press the ENTER (or RETURN) key.
The story will then respond, telling you whether your request is possible
at this point in the story, and what happened as a result.
The story recognizes your words by their first six letters, and all
subsequent letters are ignored. Therefore, CANDLE, CANDLEs, and
CANDLEstick would all be treated as the same word. Most stories don't
care about capitalization, so you can just type in all-lowercase if you
To move around, just type the direction you want to go. Directions can be
abbreviated: NORTH to N, SOUTH to S, EAST to E, WEST to W, NORTHEAST to
NE, NORTHWEST to NW, SOUTHEAST to SE, SOUTHWEST to SW, UP to U, and DOWN
to D. IN and OUT will also work in certain places.
There are many differnet kinds of sentences used in Interactive Fiction.
Here are some examples:
> WALK TO THE NORTH
> TAKE THE BIRDCAGE
> READ ABOUT DIMWIT FLATHEAD
> LOOK UP MEGABOZ IN THE ENCYCLOPEDIA
> LIE DOWN IN THE PINK SOFA
> EXAMINE THE SHINY COIN
> PUT THE RUSTY KEY IN THE CARDBOARD BOX
> SHOW MY BOW TIE TO THE BOUNCER
> HIT THE CRAWLING CRAB WITH THE GIANT NUTCRACKER
> ASK THE COWARDLY KIND ABOUT THE CROWN JEWELS
You can use multiple objects with certain verbs if you separate them by
the word "AND" or by a comma. Here are some examples:
> TAKE THE BOOX AND THE FROG
> DROP THE JAR OF PEANUT BUTTER, THE SPOON, AND THE LEMMING FOOD
> PUT THE EGG AND THE PENCIL IN THE CABINET
You can include several inputs on one line if you separate them by the
word "THEN" or by a period. Each input will be handled in order, as
though you had typed them individually at seperate prompts. For example,
you could type all of the following at once, before pressing the ENTER (or
> TURN ON THE LIGHT. TAKE THE BOOK THEN READ ABOUT THE JESTER IN THE BOOK
If the story doesn't understand one of the sentences on your input line,
or if an unusual event occurs, it will ignore the rest of your input line.
The words "IT" and "ALL" can be very useful. For example:
> EXAMINE THE APPLE. TAKE IT. EAT IT
> CLOSE THE HEAVY METAL DOOR. LOCK IT
> PICK UP THE GREEN BOOT. SMELL IT. PUT IT ON.
> TAKE ALL
> TAKE ALL THE TOOLS
> DROP ALL THE TOOLS EXCEPT THE WRENCH AND MINIATURE HAMMER
> TAKE ALL FROM THE CARTON
> GIVE ALL BUT THE RUBY SLIPPERS TO THE WICKED WITCH
The word "ALL" refers to every visible object except those inside
something else. If there were an apple on the ground and an orange inside
a cabinet, "TAKE ALL" would take the apple but not the orange.
There are three kinds of questions you can ask: "WHERE IS (something)",
"WHAT IS (something)", and "WHO IS (someone)". For example:
> WHO IS LORD DIMWIT?
> WHAT IS A GRUE?
> WHERE IS EVERYBODY?
When you meet intelligent creatures, you can talk to them by typing their
name, then a comma, then whatever you want to say to them. Here are some
> JESTER, HELLO
> GUSTAR WOOMAX, TELL ME ABOUT THE COCONUT
> UNCLE OTTO, GIVE ME YOUR WALLET
> HORSE, WHERE IS YOUR SADDLE?
> BOY, RUN HOME THEN CALL THE POLICE
> MIGHTY WIZARD, TAKE THIS POISONED APPLE. EAT IT
Notice that in the last two examples, you are giving the characters more
than one command on the same input line. Keep in mind, however, that many
creatures don't care for idle chatter; your actions will speak louder than
Basic Commands ||
BRIEF - This command causes Frotz to fully describe a location only the
first time you enter it. On subsequent visits, only the name of the
location and any objects present will be described. Most adventures will
begin in "BRIEF" mode and remain in "BRIEF" mode unless you use the
"VERBOSE" or "SUPERBRIEF" commands.
DIAGNOSE - This will give you a report of your physical condition.
Most, but not all games support this command.
INVENTORY - This will give you a list of what you are carrying and
wearing. Usually you can abbreviate "INVENTORY" to "I".
LOOK - This will give you a full description of your location. You can
abbreviate "LOOK" to 'L'.
QUIT - This lets you stop Frotz gracefully. If you want to save your
position before quitting, you must use the "SAVE" command.
RESTORE - This restores a previously saved position.
RESTART - This stops the store and restarts it from the beginning.
SAVE - This saves a "snapshot" of your current position. You can return
to a saved position in the future by using the "RESTORE" command.
SCRIPT - This command tells Frotz to make a transcript of the story and
save it to a file. Transcripts can be used to aid your memory, prepare
maps, prepare walkthroughs, make something to brag about, and so on.
SCORE - This command will show your current score and often a ranking
based on that score.
SUPERBRIEF - This one causes Frotz to display only the name of a place you
enter, even if you've never been there before. In this mode, not even
objects present are described. Of course, you can get a full description
of your location and the object present by typing "LOOK". In "SUPERBRIEF"
mode, the blank line between turns is eliminated. This mode is meant for
players who are already familiar with the geography.
TIME - This gives your the current time in the story. Some games don't
have a concept of time and therefore don't have this command.
UNSCRIPT - Stops Frotz from making a transcript.
VERBOSE - This causes the game to give a complete description of each
location and the objects in it every time you enter a location, even if
you've been there before.
VERSION - Shows you the release number and serial number of the story
WAIT - Causes time in the story to pass. Since nothing happens until you
type a sentence and press RETURN, you could leave your machine, take a
nap, then return to the story to find that nothing has changed. So, to
make time pass in the story, you type "WAIT". For example, if you meet a
wizard, you might "WAIT" to see if he will say anything. If you're aboard
a flying carpet, you might "WAIT" to see where it goes. There are few
exceptions, most notable Infocom's "Border Zone", in which the game is
played in real-time (take too long deciding what to do and Bad Things
happen). This command can often be abbreviated to "Z".