Adventure of the Week: Forbidden Planet Part I (1981)

UPDATE 12/31/2011:   A reader playing the Mac version, Futuria, noticed a couple of glitches in the walkthrough -- I had the player removing the amulet in the dark cave, which would have almost been okay had I not also included an unnecessary extra (and fatal in the "dark") move a few steps later!  I think this was a leftover step from my attempt to thwart the spear trap -- thinking that if it was dark in the room I might not get hit by it.  I've updated the walkthrough accordingly.  Thanks, Gael!

UPDATE 08/06/2011:  I received a note from the author of Forbidden Planet, Bill Demas, offering some historical corrections and additional information.  With his permission:

I just came across your review of my 30-year old adventure.  Such a long time ago.  There are a few historical errors that I think I can correct for you.  Fantastic Software was not my company, but was a local Las Vegas software company run by Al Loose at the time.  I cannot recall how I became involved with him after all this time, but he had the contact with Dick Barker about the speech synthesis and thought it would be great for an adventure game.  I was, and still am, a Las Vegas resident, but I was already in college when I started developing software on the TRS-80.  I wish I had been only 14 years old as Scott  seems to think I was!  No online service companies etc. myself, but I did go on to write many educational games for a company called Unicorn Software in the mid to late 80's on several platforms (Amiga, Apple IIgs, Atari).  I even ported the Forbidden Planet / Forbidden City adventures onto the old original B&W Macintosh and they were redistributed by Unicorn Software.  I believe the titles were "Futuria" and "Utopia", but I honestly do not remember. I'll have to have a look and see if I still have any of the packaged products. We added graphics to the adventures for the Macintosh.

Thanks for the kind words.  I do remember having a lot of fun writing in machine/assembly language back in those days.  To this day I still have several of the Z80 instructions burned into my brain.

Now back to our regularly scheduled blog post...



This week, we're exploring the first in a short-lived adventure game series -- Forbidden Planet Part I, aka Talking Adventure #1.  Two such games were written in 1981 by William Demas, best known in adventure game circles for his collaboration on Scott Adams' Adventure #12: Golden Voyage.  Forbidden Planet (no relation to the classic MGM space opera) was published by Demas' own company, (CORRECTION 08/06/2011) Fantastic Software, with a dedication to Adventure International.  I remember seeing it in a software catalog back in the day, when I could only dream of the whopping 48K of memory required to run it. Here's a vintage ad, from the December 1981 issue of 80 Micro magazine, with a remarkably pigeon-toed hero:

Unlike a lot of its contemporaries, which dive straight into the gameplay, Forbidden Planet Part I starts with a fairly detailed title screen:

The memory requirements and the Talking designation stem from short, lo-fi digitized speech samples provided by Dick Rogers Barker (CORRECTION 01/03/2011).  Aside from a few introductory phrases, most of the snippets are standard adventure response material - "Sorry?", "What?", and my favorite, "Tell me how?", because the low sample rate caused my wife to hear it as "Kill me now!", especially after umpteen repetitions.  The voice is a technically interesting novelty, but I highly recommend playing this one with the voice DEactivated.

The game is presented in mixed-case text, unusual for the TRS-80 at the time.  Plotwise, Forbidden Planet Part I is a bit of a genre hybrid -- it starts aboard a space cruiser, with the ship's alarm sounding, but eventually the player will encounter fantasy motifs, with ogres and a centaur planetside.

Interested readers are, as always, urged to explore Forbidden Planet before proceeding here.  It's a fairly difficult game, and I will be giving away the interesting details in the following discussion, along with a full walkthrough below the fold.  That is to say, there's no sign of Anne Francis here, but there are definitely...

***** SPOILERS AHEAD! *****

We begin inside a plastic cylinder, aboard a space cruiser in trouble.  To leave the cylinder, we need to GET OUT.  The parser is a standard two-word engine, with a few quirks of its own -- inventory is checked with I, not INV or INVENTORY.  SAVE GAME works, writing to disk; there's no RESTORE command, so we can only restore after dying or quitting (at which time we can choose to play with or without voice.)


There are old-school warning-free deaths a-plenty as well -- aboard our space cruiser prior to landing, OPEN HATCH yields I'M DEAD! PLAY AGAIN?

On the bridge, SIT CHAIR produces OUCH! -- because LOOK CHAIR yields I found something. It's a Disruptor, a ray-gun of sorts, with 5 charges.  The bridge's control panel has a blue button and a white button; PUSH BLUE turns on a viewscreen, where LOOK SCREEN reveals that The ship is on a collision course with a planetoid!  The white button turns on the autopilot, or attempts to; it is not initially in working order.

The puzzles aboard our cruiser are fairly linear and not particularly difficult to deal with, nor do we need to bring many items along for the second phase of the game.  To fix the autopilot, we have to unscrew a metal plate in the floor to find a crawlway, using the screwdriver found in a metal cabinet, after we unlock it with a key, of course. The cabinet also contains a box, which contains a tube, and an old rag.

I turned off the audio shortly after trying to GET WIRES below deck -- the attempt produced a fatal electrocution, and a painfully lengthy bit of speech, which I eventually realized was just reading through all of the data in memory.  It played through all of the available speech samples, and turned program code and data into white noise, until it finally got around to telling me I'M DEAD! PLAY AGAIN?  Whoops.

If we don't get the autopilot fixed, our ship eventually collides fatally with the planetoid.  It's not hard to find the faulty hardware, but I wasn't able to FIX TUBE or GET CHARRED TUBE or REPLACE TUBE.  We actually have to approach it indirectly with USE RAG, so the old charred tube shatters and we have an empty socket into which we can INSERT TUBE.

After replacing the tube we can turn off the alarm by turning on the autopilot, but the viewscreen still shows the impending collision.  The only safe course of action is to return to the plastic cylinder where we started out, and WAIT for the crash landing.

Once we're planetside, the ship EXPLODES shortly after the crash landing.  We have to get out and away from the damaged space cruiser in the few moves available before it goes up; we can discard most items we're still carrying from the ship, as aside from the Disruptor none of them are called for after this point.  But first priority is to open the hatch and get out of the ship and at least one room away, as the game's voice announces I HEAR SOMETHING EXPLODE.

We find ourselves on a planet described as Earth-like, but still strange and hostile.  We land near a Strange lake that contains a strange liquid.  Hmmmm.  DRINK LIQUID yields the expected POISON!! I'm DEAD!  GO LAKE has similarly fatal results, numbness followed by drowning.

Entering the nearby caves without a light source is dangerous in the Scott Adams tradition -- we can fall and break our neck, though if we know where we're going we can navigate safely.

Our first indication that we've left the science-fiction leg of the story behind comes when we find a leather bag on a dirt road, containing three crossbow bolts.  We find a crossbow on a mountain top, and an ogre blocks the way to a cave. We can pick up an Amulet near the dark forest, and if we
WEAR AMULET, It begins to glow. (And the voice goes insane once again, so I really recommend turning it off when the option is presented during startup and restores!)

With the amulet as a light source, we can explore one of the caves to find a shovel and an Old Book that reads, "Summon the Guardian of this land and He'll transport you ac..."   The fragment is incomplete, but we can assume it's a way to get ac...ross the strange lake.  The cave also contains another ogre, sitting up against the wall and preventing access to a hole leading to another area.

Designer William Demas begins to make our lives interesting but tricky at this point, as there are a number of possible paths and sequences available, and only one (with minor variations) will lead to ultimate success.

We can GET BOLT from the leather bag and LOAD CROSSBOW to assemble a Loaded crossbow in inventory.  But we can't KILL OGRE / WITH CROSSBOW -- we have to FIRE CROSSBOW - At what? - AT OGRE.  If we have attempted to fire the crossbow or the Disruptor previously, an AT [target] command will assume we want to use the same weapon previously employed.  We can also TIE ROPE / TO BOLT, but must do this before we load the bolt into the crossbow.  When this is done, the Other end of rope is handled as a separate inventory item, allowing us to shoot the bolt at a target and retain access to the attached rope.


The Dark Forest is a small but convoluted maze, and at first it seems like an unnecessary excursion.  But once we retrieve the axe from the other cave, we can visit the forest to CHOP one of the non-petrified trees, producing a Log and a Branch, both of which prove to be very important.

How do we get into the other cave?  Well, we can use the crossbow to kill the ogre in the first cave, revealing a hole in the wall.  But that doesn't help with this problem.  It just leads to a boulder in a dead-end passage - we can SHOOT DISRUPTOR / AT BOULDER until the charge runs down, but nothing useful happens.

We can also pick up a conch shell in this cave, where BLOW CONCH causes a cave-in, killing us; it's more useful on the shore of the strange lake, where it summons a Charon-like boatman.  But we can't cross the lake until we can pay the fare.  Even if we have no coins at all in inventory, we can try to GIVE COIN to the strange figure, but He counts the coins, looks dissatisfied and strangles me!!  Clearly we need some cash, and rounding up nine gold coins to pay the ferryman comprises most of this adventure's remaining challenge.

The pair of ogres present an interesting and fairly complex puzzle.  Killing the ogre at the mountain with the crossbow works, but causes death as he falls on us; using the Disruptor just angers him, and he squashes us.  It took me quite a few experiments to figure out that we can use the Disruptor to anger the first cave ogre, causing him to chase us all the way back to the mountain, where his arrival distracts the ogre guarding the second cave.  But the fighting ogres will eventually cause an avalanche, sealing off the cave entrance.  We need to get the axe from the cave, but escape before the avalanche occurs (it's triggered when we explore beyond the cave entrance) so we can visit the Dark Forest and come back with the Log and Branch.


Inside the cave, we find one gold coin near the entrance, where we can also DIG to find a Small bowl.  The cave is very dangerous -- it's advisable to SAVE GAME regularly here, as a number of creatures attack randomly, sometimes immediately.  For example, we can SHOOT DISRUPTOR / AT BAT to dispatch him, but sometimes we don't get the chance to do so before Bat lands on my neck and bites ME! I'm DEAD!

The cave's lower reaches feature a strange red river, where a thirsty Centaur prevents us from crossing. He holds out his hand, and if we GIVE COIN he will wander off, allowing us to GO RIVER.  But this isn't the right approach -- we need that coin, and the centaur handily deflects our weaponry with his shield.  So what we need to do is observe that the Centaur frequently drinks from a nearby well, and use the small bowl to contaminate it with the river's poisonous liquid.  He drinks, dies, and falls into the river, unfortunately taking his handy shield with him.

Now we can GO RIVER... and if we aren't carrying the log, regardless of how many inventory items we are carrying, we discover that I sink like a rock. I'm DEAD!  If we have the log, we float across easily.

There's an advertising sign on the other side of the river, Scott Adams style, promoting Forbidden Planet Part II, which did come out under the title Forbidden City.

A piece of paper nearby finishes the fragment discovered earlier, and gives us an important detail; READ PAPER reveals that It says: ross the lake.  Price for this service is 9 gold coins.  At this point we only have one coin, so further adventuring clearly lies ahead.

We can cross the nearby swamp on foot, as long as we don't stay in the muck too long, but a lurking alligator will now begin following us around, eventually attacking and killing us.  I tried to shoot him, to no avail, and lure him into the poisonous river, also with no success.  Eventually I tried to WRESTLE ALLIGATOR, which works, but only in the swamp; wrestling him elsewhere only angers him, fatally (on our end!)

With the alligator out of the way, we have a slightly better chance of dealing with the next tricky puzzle.  In the Shrine on the other side of the swamp, we find a classical amphora (vase) on a pedestal.  If we try to GET AMPHORA, a spear shoots from across the room, and we're dead once again.  We have to USE BRANCH, which knocks the amphora to the floor, shattering it to reveal some gold coins as the spear ends up embedded in the wall and a poisonous asp also appears.  Often the asp attacks immediately, so it's wise to SAVE GAME before doing this.  We have to USE BRANCH a second time, to catch the deadly snake, and trust to luck that we'll be able to survive for a few moves before Asp slithers up the branch and bites me!   If we even get that far -- sometimes the asp doesn't even wait that long:

Dealing with the asp stumped me for quite a while.  Removing the amulet and working in the dark seemed to inhibit its attack for a few moves, buying some time, but I was still dying on a regular basis.  I tried to use the bowl to pour some of the poisonous river water into the amphora before shattering it, but that didn't work.  I thought perhaps the alligator would take out the snake, but they're both more interested in attacking the player than each other.  I tried to shoot the asp with the Disruptor and the crossbow, multiple times, missing on every attempt.  I tried to THROW STICK, hoping it would take the asp with it, but it always just dropped the asp on the floor or ground, where it promptly attacked.  What I finally worked out was that we can leave the Shrine quickly and THROW ASP / IN SWAMP.  Whew!

There are a couple of annoying bugs at large here -- DROP BOWL is also taken by the parser as DROP BOW, so it drops the Crossbow if we are carrying both items.  I also ran into a situation where the bat consistently attacked me immediately after restoring, so I had to try different random actions after each die-and-restore cycle until I finally lucked out and was able to destroy the winged nuisance.

Back at the cave entrance with 8 gold coins accumulated (checking with COUNT COINS), we're still trapped by the avalanche.  LOOK UP reveals a hole in the ceiling, but it's too high to reach.  We need to use the crossbow and rope to shoot a bolt and line into the hole, allowing us to CLIMB ROPE -- but only once, so we have to take everything with us that we're likely to need later.  Oh, and we'd better SAVE GAME before trying any of this, because we can miss the hole with our one and only rope-tied-to-bolt... at least, that's what happens if we forget to LOOK UP and establish the hole's existence before we try to SHOOT CROSSBOW / AT HOLE.

Having emerged from the cave, we find that one of the ogres is dead, but the winner is still alive and has returned to his post in the other cave.  This time, we need to kill him properly with the crossbow.

Now we can explore the final sections of the game.  With the pickaxe found in the dangerous cave, we can break down the boulder in the dead-end passage and find the last coin.  With 9 coins, we BLOW CONCH on the shore to summon the boatman.  He invites us aboard his raft -- but when I tried to CROSS LAKE, the parser interpreted it as GO LAKE, ignoring the raft and drowning me.  GO CITY to the metropolis visible on the other side of the lake doesn't work either.  But GO RAFT does.

We're almost at the end here.  Once we're on the other side of the lake, at the gates of the Forbidden City, we just have to READ SIGN to get the password for Part II:  COSMIC (which saves us solving a puzzle at the beginning of the second game.)

Victory is ours -- at least, You've escaped ALIVE!

I enjoyed playing Forbidden Planet Part I  -- it's difficulties are legitimate, aside from the irritating random events, and I plan to tackle Part II in a future installment.  A full walkthrough is below the fold, and is also available at the CASA solution archive.


***** WALKTHROUGH *****





GET OUT
W
N
W
GET KEY
E
S
E
S
OPEN CABINET
LOOK CABINET (3 times)
GET BOX
GET RAG
GET SCREWDRIVER
N
W
N
W
UNSCREW PLATE
GO CRAWLWAY
USE RAG
LOOK BOX
GET TUBE
INSERT TUBE
U
E
S
PUSH WHITE (alarm shuts off)
LOOK CHAIR
GET DISRUPTOR
E
GO CYLINDER
WAIT (repeat until rough landing occurs)
GET OUT
W
N
OPEN HATCH
GO HATCH (Earth-like planet)

S
DROP BOX
DROP RAG
DROP KEY
DROP SCREWDRIVER
DROP PLATE
GO ROAD
GET BAG
W
W
GET ROPE
E
N
GET AMULET
WEAR AMULET
S
E
E
N
E
GO CAVE
GET SHOVEL
E
SHOOT DISRUPTOR
AT OGRE (ogre gets angry)
W
N
W
S
GO ROAD
S
W (ogres fight)

CLIMB MOUNTAIN
GET CROSSBOW
D
GO CAVE
DROP BAG
DROP CROSSBOW
DROP ROPE
GET AXE
GO OPENING
E
N
W
N
GO FOREST
S
CHOP TREE
GET LOG
GET BRANCH
W
N
S
S
E
S
W
GO CAVE

DROP AXE
W
DIG
GET BOWL
GET COIN
E
DROP SHOVEL
DROP COIN

(It's wise to SAVE GAME now and then in this section - creature attacks are random, sometimes frustratingly so)

S
AT BAT (got him!)

GO HOLE
FILL BOWL
FROM RIVER
POUR LIQUID
IN WELL
DROP BOWL
WAIT (until centaur drinks from well and dies)
GO RIVER (float across)

N
W
N
GO SWAMP
WRESTLE ALLIGATOR
N
GO CAVE
LOOK PEDESTAL (good time to SAVE GAME again)
REMOVE AMULET
USE BRANCH
USE BRANCH
W
THROW ASP
IN SWAMP
WEAR AMULET
GO CAVE
GET COINS
W
GO SWAMP
E
S
E
S

GO RIVER
U
GET PICKAXE
N
DROP BRANCH
GET ROPE
GET CROSSBOW
LOOK UP
TIE ROPE
TO BOLT
LOAD CROSSBOW

SHOOT CROSSBOW
AT HOLE

GET COIN

CLIMB ROPE
D
E
N
E
N
E
GO CAVE
E
SHOOT CROSSBOW
AT OGRE (surviving ogre dies)

GO HOLE
S
W
DROP LOG
GET CONCH
W
USE PICKAXE
GO TUNNEL
DROP PICKAXE
GET COIN
COUNT COINS (should have 9)

S
E
E
N
GO HOLE
W
N
W
BLOW CONCH (strange figure appears)
GIVE COINS (summoned aboard raft)
GO RAFT (arrive at city)
READ SIGN (receive password for Part II, Forbidden City)