The engine

A fixed fact, crossed with a rule.

Most stories for this age hand a child a neutral world and ask them to imagine over the top of it: a chair becomes a hotel, a rug becomes the sea. Tocko goes the other way. The stair does not become a mountain — it stays a stair, and the game is about the stair being a stair.

Take story 2.

The fact. The eleventh stair squeaks. It has always squeaked.

The rule Pim makes of it. You have to get all the way up to Number Three, and if the eleventh stair squeaks you go back to the bottom and start again.

What the building says. KREEE-onk

What she wanted. Pim wants the last of the good bread upstairs before it is opened without her.

That is the whole method. The fact is not negotiable and is written down before the story is; the rule is a four-year-old's, so it is confident, slightly wrong, and applied without mercy to everybody present.

The building is never magic. Pim decides the noises are answers, and the book never says whether she is right.

The engine

Every square is a story that could exist.

28 fixed facts about one building, crossed with 8 kinds of rule a four-year-old invents. That is 224 games before anybody finds a new fact — and every story finds one. 52 cells are spent.

F01F02F03F04F05F06F07F08F09F10F11F12F13F14F15F16F17F18F19F20F21F22F23F24F25F26F27F28Make-It-AnswerBeat-ItDo-It-BackwardsGet-It-To-Say-Your-WordDon'T-Wake-ItOnly-One-MayName-It-From-The-SoundFind-The-Odd-One

52 written172 still openPick a lit square.

Any squareThe fact stays fixedThe rule is what changes. Hover or tap a brass square to see which story that pairing turned into.

The eight beats

The same shape, fifty-two times.

1	Hook	Pim is already moving by the eighth word.
2	Want	What she is after, and the fixed fact standing in the way.
3	Try one	The rule, said out loud, and the first honest attempt.
4	Try two	Somebody else has a go, usually worse and much louder.
5	Turn	The building does something nobody expected.
6	Reverse	Pim goes back over it in her head and hears what it meant.
7	Settle	Who won, who lost, and the tapper goes on the board.
8	Close	Two taps, and wait for the tock.

A cutaway drawing of Tocko: five floors of flats, the Hall at the bottom with its letterboxes and tapper board, the courtyard, and the boiler room under the ground line.

The cutaway: five floors, the Hall, the courtyard and the Under.

The fact log

28 fixed facts, and where each one lives.

These are written down before the stories are, and they do not change afterwards. If a story needs the eleventh stair to be silent, the story is wrong.

4 factsThe StairsThe eleventh stair squeaks. It has always squeaked

4 factsThe MiddleIt gives your voice back exactly once, and only the last word survives

3 factsThe Up-DownNine seconds between floors, every time

4 factsThe HallTwelve letterboxes, and each one thumps differently

2 factsThe Green DoorPush and lift at the same time, or nothing

3 factsThe Drying RoofThe tank gulps twice whenever anybody turns off a tap

3 factsThe UnderThe boiler breathes once every two seconds, always

2 factsThe Back StepsThe bin lid is the loudest object in the world

3 factsNumber Three / Number FiveThe cold pipe goes up through Number Five's floor

Questions

How it works.

How are Tocko stories written?

One fixed fact about the building is crossed with one of eight rule-types a small child actually invents. The pairing is the game; the game is the story. There are 28 facts and 8 rule-types on the board, which is 224 pairings.

Why does every story have the same eight beats?

So a child who has heard three of them knows where they are in the fourth, and can join in. The shape is fixed and the fact is fixed; the only variable is the rule Pim invents.

Is the building magic?

No, and this is the load-bearing rule. Tocko creaks, ticks, drips and bangs exactly as much as a real old building does. Pim decides those noises are answers. The book never says whether she is right.

Will there be more?

No, and the arithmetic is published. There are 28 fixed facts and 8 rule-types, which is 224 cells before a single new fact is found. One new fact is found per story, so the grid grows eight times faster than it is spent. 52 of the 224 cells are used.