THE PEN AND THE DARK
Mosaic, 1984
====================
Solution by Exemptus - October 2022
Overview and general hints:
---------------------------
This is one of Mosaic's earlier efforts and one of the few games written by
Keith Campbell. It is based on a short story from the sci-fi compilation "The
Unorthodox Engineers" by Colin Kapp. This book tells some stories about a band
of engineers that solve complex problems related to alien technology. We play
the part of Fritz van Noon, leader of the Unorthodox Engineers, who has been
called to the planet Ithica by Dr. Maxwell Courtney to face the problem of The
Dark. The Dark is a gigantic mushroom-shaped structure of unknown origin which
is totally black and seems to absorb all forms of energy. The shadow cast by the
Dark's dome over the surface of the planet is called the Pen, short for
Penumbra. It is a zone where strange physical phenomena take place. Our goal is
to find out the nature of the anomaly and somehow solve its mystery.
The original story was provided with the game (as with other Mosaic text
adventures), and is absolutely necessary to complete it, because otherwise some
key information needed to play it would be missing; but, sadly, the story is not
sufficient, as some other key information was only provided with a hint sheet
that was separately ordered. More about this later. The game follows the plot of
the story very closely, but the player must fill in many of the operational
details.
This is a BASIC game, not sophisticated at all, and quite small (about 35-40
locations, depending on how we count moving vehicles), but it is amazingly
complex to solve for its size. The complexity comes from the fact that we need
to figure out an engineering problem: to assemble the necessary components of a
machine that pierces the Dark so that we can enter it, and manage the logistics
of getting said components to the right place. Even if the story essentially
tells us what we need to do, the amount of drudgery needed to put all the pieces
together is much higher than expected.
The vocabulary is more or less standard, but includes many specific verbs given
the nature of the tasks. HELP gives some of the least obvious, such as CONNECT,
DISMANTLE, LIFT, HITCH, CUT, MODIFY or LOWER, all of which are used at least
once. SCATTER and MOUNT are also necessary once, and REQUISITION several times,
although these are not mentioned. There is no score, directions can be
abbreviated (except IN, which is always "GO <place>"), and we can't really
die,
although the game can be put in an unwinnable state rather easily unless we are
careful.
The different vehicles and contraptions that appear in the game can be quite
confusing. The basic idea is to fire a cannon using a concrete pipe that can be
used to insert a titanium tube into the Dark. In order to carry the tube, pipe,
and other heavy, non-carriable objects, a trailer is needed which we can put
things onto. The trailer and other heavy machinery (like a generator) can be
towed by using a crawler, which is a vehicle we can operate, and both the
trailer and the cannon can be PULLed to move them around. But nothing can go
very deep into the Pen, us included, unless we are driving the crawler, and
properly protected, so several journeys to the edge of the dark are needed
to carry all items to the right location. In addition, the cannon needs to be
modified for it to be fit for purpose.
Hints outside the game proper, apart from the plot itself, are:
* Not all available objects appear in descriptions. The most glaring omission is
the crawler itself, which is in the vehicle park and can be ridden, but the
game only mentions it once we have been inside.
* There is a store which can provide some necessary objects on demand, but we
don't know in advance what those are. The game will tell us under the right
circumstances (basically, trying to do something without the proper equipment
in hand).
* In order to provide objects, the automated store dispatcher asks for an
"allocation code". There are no clues about the right code to enter, except
for the hint sheet that could be ordered from Mosaic. This is totally unfair
to the player, and ethically unsound, since it is basically impossible to
complete the game without ordering the hints or reverse-engineering the game
logic. Mosaic weren't the only ones abusing their customers in this way, to be
fair, but that does not make the practice less wrong. In any case, the right
allocation code is any sequence of characters whose ASCII codes add up to 281
exactly. So Q2222 is a perfectly valid code, as we have
81 + 50 + 50 + 50 + 50 = 281. But any other sequence with the same property
will be accepted as well.
The game is almost deterministic. There are a couple of random items, the most
annoying of which is that there is a button to turn the crawler 90 degrees
around (we only need to make 180 degree turns in the game), but this is only
reliable outside of the Pen. Within the Pen, the crawler turns a random number
of quarter turns with each press of the button, simulating the difficulty of
getting our bearings there. Dealing with this effect will requires patience.
Walkthrough:
------------
[We start in a flying vehicle, a scudder, flying over Ithica. The scudder will
land on its own after a few turns. We can see a view-screen and a hatch, and
there is a letter here.]
INVENTORY [We have some coins]
EXAMINE COINS [Exactly three]
GET LETTER
READ LETTER [Dr. Courtney, telling us to watch the screen; something falls out]
EXAMINE SCREEN [A nuke is dropped into the Dark, which is absorbed]
LOOK [A voucher is on the floor]
GET VOUCHER
READ VOUCHER [It's for ski equipment]
DROP LETTER [No longer needed]
[At this point, the scudder lands, after which we can go through the aft hatch.]
GO AFT
[Several questions are asked by Customs Control. The right answers are given in
the story.]
[Full name?] FRITZ VAN NOON
[Profession?] ENGINEER
[Type?] UNORTHODOX
[Sponsor?] MAXWELL COURTNEY
[We are cleared and back in the flight deck. From now on, we can enter and exit
the scudder directly.]
GO AFT
D [We are at the spaceport disembarkation area]
EXAMINE SCUDDER [There's an access door to the engine]
OPEN DOOR
GO DOOR [There is a titanium tube here; make a note of it for later]
GO OUT
[The area around the spaceport is not large. We can explore, but the first order
of the day is to visit Dr. Courtney's office, as there are some hints there.]
S
GO DOOR [The office; there is a desk and a wall chart here]
EXAMINE DESK [Kind of a poem-hint, and there is also a message]
READ MESSAGE [It suggests a visit to the Pen]
EXAMINE CHART [We see a diagram of the Pen and the Dark]
GO OUT
N
E [Fountain]
[If we try buying things in shops with our coins, we'll find they don't accept
Terran currency. But there is another use for those.]
THROW COINS INTO FOUNTAIN [Three thoughts occur to us]
[This is a bit of a forced device by the game to provide hints, but we'll accept
it. The three thoughts are "random scatter", "laser light" and "stores
cable".]
S [Into the gift shop]
[Here there are four objects: a torch, ski-wear, a compass, and an Ithican
surprise. The latter is a bit intriguing.]
EXAMINE SURPRISE [A drink, made by Order of the Immaculate Perception monks]
[This is a useful item, which we note for later. It's quite obvious that the
liqueur will temporarily enhance our perceptual powers. We need this for a very
specific thing, which will be pointed out.]
EXCHANGE VOUCHER
INVENTORY [We now have the ski-wear, which is the only ski gear in the shop]
GO OUT
[First, we will need to experiment with the Physics in the Pen, for a dossier to
be generated. This will also trigger the arrival of an authorization pass card
which we'll need to requisition items without the need to pay. But the Pen is
numbing cold, so the ski-wear is necessary to hold out there for the right
number of turns we'll need to make our scientific observations. We'll need two
additional items as well: a rock, which we'll find in the Pen, and a thermometer
to read temperatures.]
W
S
S
S
S [Research lab, there's a thermometer here]
[There is also a security door here as well, which we'll need our pass to open.]
GET THERMOMETER
N
E [Note there's a concrete pipe here]
N [Vehicle park; there's a generator and a trailer here]
[Plus the crawler, which is not mentioned in the description, but appears in the
story. It will be useful to explore it a bit now.]
GO CRAWLER [It has buttons labelled START, STOP, TURN AND FORWARD]
PRESS START [It says we need to wear a null-pressure suit to operate it]
[We don't have such a thing yet, but we take note.]
GO OUT
E
E
E [About to enter the Pen]
E [Within the Pen, where it's cold]
WEAR SKI [A lot warmer]
[We are told that observations of temperature and gravity would be useful. By
the way, while in the Pen, it's possible a small lightning cloud will show up,
at random. This has no ill consequence and can be ignored.]
E [There's a small rock here]
GET ROCK
THROW ROCK [It appears to lose kinetic energy fast]
READ THERMOMETER [Only 15 degrees lower than outside, but it feels much colder]
E
[At this point, we'll probably faint from the effort and pass out. We come to on
a park bench by the fountain, as we are rescued and taken back automatically. If
this does not happen at this point, keep going E until it happens.]
DROP SKI
DROP THERMOMETER [No longer needed]
U [At the fountain]
W
S
GO DOOR [At the Office again; this time, we see a dossier and pass card]
READ DOSSIER [We see some speculations about the nature of the Dark]
GET CARD
EXAMINE CARD [There's writing and a photo of van Noon]
READ CARD [We have full powers of requisition]
[Now we'll start assembling the machinery. The cannon is the first thing we need
to get done.]
GO OUT [We realize that we'll need special clothing and transport]
S
S
S [Lab again, but this time we can open the security door]
INSERT CARD [We are in the munitions store]
GET SUIT [The other objects are not yet needed]
WEAR SUIT [We can drive the crawler now]
W
N
E
N
N [There is a monument here]
EXAMINE MONUMENT [Mounted on the plinth there is a cannon]
PULL CANNON
S
[The cannon is too heavy to be taken, but it can be moved between locations by
PULLing it and then moving in the direction we want. The trailer behaves the
same way. We will pull the cannon all the way to the workshop, where we can work
on it.]
PULL CANNON
S
PULL CANNON
W
PULL CANNON
W
PULL CANNON
W [We are in the Workshop now]
[The idea is to try to MODIFY the cannon repeatedly for the game to tell us what
we are yet missing. But before we burden ourselves with unnecessary objects, we
will take a shortcut and do the last necessary piece first: we will need a metal
ring. It is not obvious at all where to get it, but we'll find it soon. Remember
the monks' liqueur? The ring can be found in the fountain, and we can only see
it if our perception is enhanced. But it is very heavy, so we'll need the
trailer to carry it around. So we will position the trailer first.]
GET SPANNERS [We will need them to dismantle the fountain]
GO OUT
E
N [The trailer is here]
PULL TRAILER
N
PULL TRAILER
W
[OK, the trailer is at the fountain now. But although it will allow us to move
the ring, we need a means to lift the ring in the first place.]
W
W
S [Maintenance area, there are some shear-legs here]
GET LEGS
[The shear-legs is a lifting device that allows us to LIFT and LOWER very heavy
objects, but not move them. We need a trailer for that purpose. If a trailer is
on the same location where we LIFT something with the shear-legs, we will be
given the option of LOWERing it onto either the ground or the trailer. But we
have to do this quickly, because the legs will buckle under the weight of the
lifted objects if we hold these for more than one turn. Curiously, the legs are
carriable.]
N
E
E
S [Gift shop again]
REQUISITION SURPRISE [We have it]
GO OUT
DROP LEGS [We can't use the legs if we are carrying them]
SIT DOWN
DRINK SURPRISE
EXAMINE FOUNTAIN [We now see a ring that we didn't before]
U [We need to do this standing up]
DISMANTLE FOUNTAIN [UNBOLT RING also works here]
LIFT RING
LOWER RING [Onto what?]
TRAILER [The steel ring is in the trailer]
DROP SURPRISE [Won't need it again]
PULL TRAILER
W
PULL TRAILER
S
PULL TRAILER
S
PULL TRAILER
S
PULL TRAILER
W [At workshop again]
MODIFY CANNON [To hold the parts together we need nuts and bolts]
[So the game is telling us to find nuts+bolts (these are the same object). This
is what the store is for.]
GO OUT
N
W [Store; there is a keyboard here]
READ SIGN ["Not all items on stock are on display"]
TYPE NUTS [Allocation code please?]
Q2222
INVENTORY [We have the nuts+bolts]
GO OUT
S
W
MODIFY CANNON [We need to make some holes in the gun]
GET DRILL
MODIFY CANNON [Brackets and flanges will be needed]
[Another object to get from the store.]
GO OUT
N
W
TYPE BRACKETS
Q2222
INVENTORY [We have brackets+flanges now]
GO OUT
S
W
MODIFY CANNON [Looks grotesque but serviceable]
[Finally! We now have a cannon we can use. Now we can start preparing to carry
all the machinery we need to the edge of the Dark. In order to get there we'll
need to drive the crawler, which can also tow things (the trailer, for
instance). We can start leaving all necessary things in the vehicle park. First,
the cannon itself.]
DROP SPANNERS
DROP DRILL
PULL CANNON
GO OUT
PULL CANNON
E
PULL CANNON
N [The cannon is now in the vehicle park]
S
W
W
W [Workshop again]
PULL TRAILER
GO OUT
PULL TRAILER
E
[The trailer is now where the concrete pipe is. We'll need the shear-legs again
so we can LIFT it.]
N
N
W
GET LEGS
E
S
S
W
DROP LEGS
LIFT PIPE
LOWER PIPE [Where?]
TRAILER
PULL TRAILER
N
[Let's check: we should now be in the vehicle park and have here the modified
cannon, generator, trailer with the concrete pipe on, and crawler. If so, we can
continue with the tedious part of getting all this equipment to the edge of the
dark. Let's hope all goes well once there. For reasons that will be clear later,
we'll do a dry run first: only the crawler, nothing else attached.]
GO CRAWLER
PRESS START [The engine starts]
PRESS FORWARD [The crawler starts moving]
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
[At this time, the game should tell us that we have stopped against some debris
and changed course, and we proceed at our own risk. We can try seeing where we
are.]
EXAMINE SCREEN [A searchlight would be needed to see through this gloom]
PRESS FORWARD [We have hit something and the engine has stalled]
GO OUT [We have hit the Dark and dented it by a few millimetres]
[We can see we are at the Edge of the Dark. This location is only reachable by
driving the crawler. Despite the appearance of exits, it is impossible to move
in any direction on foot. We may as well try crossing into the Dark. I'll move
E, but in reality just a few turns have to pass, since we cannot really move
anywhere else.]
E
E
E [A thought occurs that the crash means there's a lag in the Dark's reaction]
E [What is needed is a tunnel through the Dark]
E
[At this point, we faint again and have to be rescued by our team and taken back
to the Office. However, the key idea has occurred to us, which is the need to
bore a tunnel. Besides, we now know we need a searchlight, which we can ask for
at the store. If you remember the thoughts from the coins in the fountain, there
was also laser light (there is a laser in the munitions store), stores cable
(which suggests we'll need to ask for cable as well) and random scatter, which
we won't need until the end. This rescue back to the Ithica spaceport also means
that the crawler is back in the vehicle park, and if we had been towing anything
then it would also be, which is the reason we did this "dry run" first.]
INVENTORY [We only have the card, meaning we need another null-pressure suit]
GO OUT
S
W
TYPE SEARCHLIGHT
Q2222
TYPE CABLE
Q2222
INVENTORY [Check you have the card, searchlight and cable]
GO OUT
S
S
INSERT CARD
GET SUIT
WEAR SUIT
GET SHELLS
GET LASER
W
N
E
N [Vehicle park]
HITCH CANNON [We now have the cannon in tow]
GO CRAWLER
MOUNT SEARCHLIGHT [The searchlight is connected and will work automatically]
PRESS START
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD [We cannot go any further]
[It takes 7 moves from the vehicle park to the edge of the dark, where we must
leave our equipment. In practice, just repeat PRESS FORWARD until the game says
that forward movement is not possible in that direction.]
GO OUT
UNHITCH CANNON
DROP CABLE
DROP LASER
DROP SHELLS
[OK, the cannon and other carriable equipment are in place. Next we'll go back
for the generator, as we need an energy source for the cannon.]
GO CRAWLER
PRESS TURN
[A secondary difficulty arises here. In the pen, PRESS TURN has random results,
so we don't know if the crawler is correctly rotated. We need to PRESS FORWARD
and see: if the message is "A rough ride" then we are incorrectly oriented, and
you need to PRESS TURN then PRESS FORWARD until the message is "We are near the
Dark" on the first move and "The crawler lumbers forward" on the second, which
is the signal that we are going in the right direction.]
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
HITCH GENERATOR
GO CRAWLER
PRESS TURN
PRESS TURN [The crawler is now facing away from the spaceport again]
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
UNHITCH GENERATOR
GO CRAWLER
PRESS TURN
PRESS FORWARD [Repeat these two last commands as needed]
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
[Next is the concrete pipe. However, we'll need the legs to lower it once by the
Dark, so we'll get them.]
S
W
GET LEGS
N
HITCH TRAILER
GO CRAWLER
PRESS TURN
PRESS TURN
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
DROP LEGS
LIFT PIPE
LOWER PIPE [Ground or trailer?]
GROUND [Done]
GET LEGS
GO CRAWLER
[We do not unhitch the trailer here. This is because we are missing one
component: the titanium tube itself that is going to be bored through the Dark.
We know where to find it because we have seen it in the scudder's engine room,
but it is heavy and we'll need the legs & trailer combo to move it to the
crawler's location.]
PRESS TURN
PRESS FORWARD [Repeat these two last commands as needed]
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
UNHITCH TRAILER
[Now we need to get the trailer to the engine room.]
PULL TRAILER
N
PULL TRAILER
W
PULL TRAILER
W
PULL TRAILER
GO DOOR
DROP LEGS
[And that's that. Of course, if we try to LIFT TUBE now, the game will tell us
that the tubes need to be detached from the ship's hull somehow, so we need a
means to cut the tube loose.]
GO OUT
S
S
S
W [Workshop]
GET CYLINDERS [Oxy-acetylene, ideal for cutting and welding metal]
GO OUT
N
N
N
GO DOOR
CUT TUBE
DROP CYLINDERS
LIFT TUBE
LOWER TUBE [Where?]
TRAILER
GET LEGS
[We have all we need now. Let's take the tube to its destination.]
PULL TRAILER
GO OUT
PULL TRAILER
E
PULL TRAILER
E
PULL TRAILER
S
HITCH TRAILER
GO CRAWLER
PRESS TURN
PRESS TURN
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
PRESS FORWARD
GO OUT
UNHITCH TRAILER
DROP LEGS
LIFT TUBE
LOWER TUBE [Where?]
GROUND
[It remains to fire up the laser, which we have brought the generator for.]
GET CABLE
CONNECT CABLE [To what?]
GENERATOR [Done]
CONNECT CABLE [To what?]
LASER [Though attenuated, the thin laser is enough to illuminate the scene]
GET SHELLS
FIRE CANNON
SCATTER SHELLS [At random distances from the cannon]
FIRE CANNON [By firing at random intervals, the tube goes into the dark]
GO TUBE
GO FORWARDS
GO FORWARDS [Central core]
E
E
E
[Suddenly, the last veil breaks, the Dark implodes, and we vaguely get to see
some alien forms ascending, towards the sky. After this, we are rescued,
revived, and back in the Office, where Dr. Courtney finally appears and hands us
a new dossier.]
READ DOSSIER
[The dossier explains how the Dark worked and why we managed to destroy it, but
it is better explained in the story. The important thing is that we have won.
End of game.]
