Key & Compass presents:
Acid Rain
by Garry Francis

Acid Rain is a Z-machine interactive fiction game written with Inform 6 and is © 2021 by Garry Francis. It was an entry in Parsercomp 2021 where it took 8th place.

In this old-school-style escape game, you play as someone whose car battery dies while driving in deadly acid rain. You go to a nearby mansion for help, but soon find yourself trapped inside! You must build an electronic door opener from the scattered electronics in the house if you want to escape.

This solution is by David Welbourn, and is based on Release 1 of the game.

SPOILERS AHEAD. Reading a walkthrough prematurely can sometimes diminish one's enjoyment of an interactive fiction game. Please make an honest effort to play the game before reading this walkthrough.


Map 1: Outside

InsideYour Car In Front ofYour Car OutsideYour Car BehindYour Car Entranceto Mansion FrontPath FrontPorch EntryFoyer in out

Map 2: Ground floor

FrontPorch SecretRoom Scientist'sStudy EntryFoyer Library Bend inHallway Bedroom North Endof DiningHall N. Endof LongHallway PrivateBar CAUTION:Floorcollapsesafter onetraversal Ledge S. Ledge MiddleDiningHall Middleof LongHallway Kitchen GuestRoom SouthDiningHall SouthernEnd ofHallway WesternEnd ofHallway JunctionofHallways EasternEnd ofHallway Landingat Topof Stairs Landingat Bottomof Stairs AccessHallway BroomCloset Bathroom jump d u u d

Map 3: Upstairs

Balcony Storeroom N. Endof WideHall SmallCloset Ledge UpstairsLavatory Middleof WideHall TV Room Darkroom UpstairsBedroom UpstairsBathroom S. Endof WideHall LoungeRoom West Endof ShortHall East Endof ShortHall Landingat Topof Stairs Landingat Bottomof Stairs LinenCloset d u

Map 4: Basement

WesternEnd ofHallway Laboratory AccessHallway StorageArea ElectronicWorkshop TinyRoom d u


Inside Your Car

> turn key. (Car doesn't start.)

> x car. x key. x ignition. x wheel. x knob.

> x dashboard. x glovebox. x seat.

> open glovebox. x coat. x torch.

> take coat, torch, key.

> wear coat. pull knob. (to unlock the car's bonnet)

CAUTION: If you're not wearing your raincoat, the acid rain kills you.

> out.

Outside Your Car

> x rain. x car. x mansion.

> w.

In Front of Your Car

> x fence. open bonnet.

> x engine. x battery. (must replace it)

> close bonnet. e. e.

Behind Your Car

> unlock boot with key. open boot.

> x tyre. x lever. take lever.

> close boot. w.

Outside Your Car

While you can lock the car with the key, you don't need to.

> s.

Entrance to Mansion

> x gate. x chain. break chain with lever.

> open gate. s.

Front Path

> x lawn. s.

Front Porch

> x door. knock on door. push doorbell. open door. (locked)

> x pot. x plant. look under pot. (too heavy to move)

> take plant. look in pot. take brass key.

> put plant in pot.

> unlock door with brass key.

> open door. s.

Entry Foyer

> e. (You need light.)

> turn on torch. e. (The front door slams shut!)

> read sign. (You need an opener.)

> e.


> x book. read it. open it. read it.

To make an electronic door opener, you need a screwdriver, a soldering iron, and the relevant parts.

> read note. (Lists the eight parts you need.)

You can ignore the table, shelves, and other books.

> w. w.

Scientist's Study

> x card. read card. x switch. take all.

> e.

Entry Foyer

Because there's an inventory limit and no convenient portable container in this game, you should choose a few locations to drop objects in that you don't need immediately. Drop the book and note if you took them.

By the way, the torch's batteries won't last forever. But the author has been kind enough to put some spare batteries in the ground floor bathroom's vanity drawer, and walking around in the dark won't kill you.

> drop car key, brass key, lever.

> s.

Northern End of Long Hallway

> e. (A monster stops you.)

> x monster.

> w.

North End of Dining Hall

> x sideboard. x bowl. x banana. take it.

> s.

Middle Dining Hall

> x table. x dish. x caviar.

> take dish. (no: too delicate)

> e. e.


> x sink. open cupboard.

> x crackers. take them.

> w. s.

Southern End of Hallway

> x metal door. put card in slot. (Metal door opens.)

> x wooden door. open it. (locked)

> w.

South Dining Hall

This room is empty.

> e. e.

Western End of Hallway

Note the stairs going down.

> e.

Junction of Hallways

CAUTION: Going north from here is one-way because the floor will collapse.

> s.

Broom Closet

> x broom. take it.

> n. e. s.


> x vanity. open it. take batteries.

I can't predict when the torch's light will fail, but when it does, just put batteries into torch, and it'll work again.

> x basin. x mirror.

> n. n.

Guest Room

You can ignore the bed and its clean sheets.

> x window. open window. n.

Southern Ledge

> take red key. (too far)

> take red key with broom. (success, but the broom is gone)

> jump.


> open window. n.


> x keypad. (has 16 letter buttons)

> x message. read it. (It's a cryptogram.)

> x sheets. move sheets. x body.

> w.

Bend in Hallway

> s.

The floor caves in, but you're back at...

Junction of Hallways

> w. d. w.


> x gorilla. give banana to gorilla.

CAUTION: If you don't take the peel, you will slip on it and die when you try to open the cage.

> take peel.

> open cage. put peel in cage. take white key.

> e. s.

Electronic Workshop

Since the soldering iron can't be taken, you'll be making the door opener here. I suggest putting all the components and the screwdriver on the bench here when your inventory is full or nearly so.

> x soldering iron. x components. x board.

> x bench. x door. open it. (locked)

> put switch on bench.

> take board. put it on bench.

> n. e.

Storage Area

> x coil. take it.

> w. s.

Electronic Workshop

> put coil on bench.

> n. u. w.

Southern End of Hallway

> unlock wooden door with red key.

> drop red key. open wooden door.

> s. u. n. w.

Upstairs Bathroom

> open vanity. x box. take it.

> x mirror. read it. ("RUTH WAS HERE")

> n.

Upstairs Lavatory

You don't need the toilet paper, but:

> x paper. read it. ("LED under sheets in linen closet")

> s. e. n.

Middle of Wide Hall

> x sealed door. n.

Northern End of Wide Hall

> unlock white door with white key.

> drop white key. open white door.

> w.


> x transducer. take it.

> e. n.


> x macaw. give crackers to macaw.

Molly, the macaw, will now follow you and give hints.

> x trellis. x vines. x fruit. take fruit. x fruit.

> ask Molly about fruit. (for goat)

> ask Molly about caviar. (for monster)

> s. e.

Small Closet

> x coats. search coats.

The revealed opening is south.

> s.

TV Room

> x remote. take it.

> x TV. turn it on. turn it off.

> n. w. s. s. e.

Lounge Room

> x glasses. take them. wear them.

> e.

West End of Short Hall

> open louvred door. s.

Linen Closet

> x sheets. look under sheets.

> x LED. take it.

> n. e.

East End of Short Hall

> x goat. give fruit to goat. (It falls asleep.)

> n.

Upstairs Bedroom

You can ignore the bed and its clean sheets.

> x window. open it. n.


> x silver key. take it. (can't: soaked with acid rain)

> s. s. w.

West End of Short Hall

> open plain door. n.


This is an optional exercise for a clue you probably don't need.

> x bench. x chemicals. x tools. x enlarger. x film.

> x lamp. turn it on.

> close door. turn off torch. (Only want red light.)

> take film. develop film.

> x negatives. take them. put them on enlarger.

> read negatives. ("Code is alphabet reversed")

> open door. turn on torch. turn off lamp.

> s. w. w. s. d. n. e. d. s.

Electronic Workshop

> put LED, remote, transducer, box on bench.

> n. u. w. w. n.

Middle Dining Hall

> take caviar. n. e.

Northern End of Long Hallway

> give caviar to monster. (It dies!)

> x monster. e.

Private Bar

> x bottle. take it.

> w. s. e.


You can fill the bottle with water from the kitchen or from either bathroom.

> fill bottle with water.

> w. s. e. e. e. n. n. jump. n.


I'm assuming you're still wearing the UV spectacles.

> read message. ("VZX")

> type VZX. (A hidden panel opens to the north.)

> n.

Secret Room

> x module. take it.

> x journal. read it. open it. read it.

> x notes.

> s. s. jump. s. s. w. w. w. s. u. n. e. e. e. n. n.


> pour water on silver key. take silver key.

> s. s. w. w. w. s. d. n. e. d. s.

Electronic Workshop

> unlock door with silver key.

> drop key. open door. e.

Tiny Room

> x tools. g. g.

> take screwdriver and car battery.

> w.

Electronic Workshop

You should now have everything you need either on the bench or in your inventory:

> make opener. take opener. x it. (It has a button.)

> n. u. w. n. n. n.

Entry Foyer

Don't forget to pick up your own stuff:

> take car key and lever.

> push button. open door.

> n.

Front Porch

Molly says "bye" before flying away, ignoring the acid rain.

> n. n. n.

Outside Your Car

I'm assuming you left your car unlocked.

> in.

Inside Your Car

> pull knob. out. w.

In Front of Your Car

> open bonnet. put new battery in bonnet.

> close bonnet.

> e. in.

Inside Your Car

> put key in ignition. turn key.

> drive car.

*** You have won ***





This is the response to ABOUT:

In the 1980s, I wrote an adventure column for the UK Atari magazine 'Page 6'. Around 1987, the editor sent me a disk of five home-brew adventures to review. I played all the games and sent review comments, which were forwarded to the authors, but, for some reason, the games were never published.

I can no longer read the disk with the original adventures, so I decided to recreate them from my map and playing notes.

The first of these was an Atari BASIC program called 'Breakdown' by an unknown author. I rewrote this from scratch and expanded it to create 'Acid Rain' for ParserComp 2021.

Concept by unknown author.
Game design and coding by Garry Francis.
Testing by Andrew Schultz, Dee Cooke, Giannis Georgiou, Mike Carletta, Jade, Jonathan and Rovarsson.


There's a coded message in the main bedroom:


The cipher is the alphabet backwards, which you'll be told if you solve the photography puzzle in the darkroom:




You have an inventory limit of eight items, not counting items you're wearing.

Door opener components

The note lists all eight components you need. Take all the components and the screwdriver to the electronic workshop, then make opener.


You don't need to carry any of these readables around. Just read them and leave them where they are.

Other stuff

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