How to play Secret Codes

Twenty-five words, and two keys that do not agree

The words go face up where you can both see them. Behind them are two different keys, one each. Yours says which nine of the twenty-five are yours to find, which three would end the mission on the spot, and that the rest are nobody's. Theirs says something else about the same twenty-five words.

Three of the nine are on both keys, so between you there are fifteen words to find. Your key never reaches your partner's browser and theirs never reaches yours — not at the end of a turn, not when the clock runs out, not until the mission is over. Every relabelling of their key you cannot rule out produces a byte-identical page from your seat, and a test in the suite fails if that stops being true.

Say one word and a number, and let them read your key

You take it in turns. Whoever is speaking says a single word and a number; the other one touches words; and it is the speaker's key that decides what is under each of them. Touch one of theirs and carry on. Touch one their key calls nobody's and the turn is over — but that only means the word is not one of theirs, and it may still be one of yours, so do not cross it off.

That is the part that catches everybody, and it is why a word can be struck from one key and still be live from the other. There is one word on your key that is the word that ends everything for them, and you have to get them to say it without ever being able to warn them.

Fifteen words in nine turns, and then no more clues

Nine turns against fifteen words is nearly two a turn, which is the whole pressure. A pair who only ever say ones are right about every word they name and lose anyway; somebody has to say a three eventually, and working out which of you it should be is the game.

When the turns run out with words left there are no more clues. You keep touching, going only on what was already said — and now a word that is nobody's ends it too. Find all fifteen and you have both won; there is no other way to win and no way for only one of you to.

Questions people ask

Is this the same game as Our Words with fewer people?

No. Our Words is two sides trying to beat each other with one key between them; this is two people on the same side with a key each, and the keys disagree. They share a deck of words and nothing else. If you have six colleagues on a call, you want Our Words.

Can two of us play round one screen?

Not this one. The board is public and the two keys are not, so it needs a screen each, in separate corners, and the talking done out loud. Our Words is the one where five people can watch a single board.

Why is a word I know is mine the dangerous one to press?

Because your key has no bearing on what your partner's says. Of your nine, three are theirs, five are nobody's to them, and one is the word that ends it — so a word you are certain about is more likely to end the mission than a word picked blind. It is the most counter-intuitive thing in the game and the panel tells you once, at the moment you are about to press one.

Does anybody have to install anything to play Secret Codes?

No. It runs in the browser everyone already has open. One person opens a room, reads out the six-character code or pastes the link into the channel, and everyone else is at the table in a couple of seconds.

Do we need accounts?

No. There is no sign-up, no password and no email address anywhere in the flow. You pick a name when you sit down, and that is the whole of it.

How many people can play Secret Codes?

1 to 8 — best with two. A room seats up to 12.

How long does a game of Secret Codes take?

About 15 minutes, which is the length of a coffee break rather than the length of a games night. Nobody is the host in the sense of holding the controls, so a round finishes whether or not everyone is still looking at it.

Does it work over a video call?

That is what it is for. The game is on the screen and the talking is on the call — nobody has to describe a board to anybody, and the parts that must stay private stay on the server rather than being read out.