Defuse!

Full rules

1. Overview
2. The cards
3. Setup
4. Talking
5. Playing a turn
6. End of the game
7. Worked example
8. Tips for beginners
9. Variants

Overview

Defuse! is a cooperative card game: all players form one team and win or lose together. A bomb lies on the table – a row of face-down cards, the wires. One player, the expert, knows the secret code: the suit of every wire. The others are the defusers. They must cut the wires from left to right, each with a card of the right suit from their hands. The catch: the expert may not say a word. Their only way to help is to lay one of their four Kings next to a wire as a hint.

Every wrong cut makes a spark, and a fuse burns down with every turn. Too many sparks, or a burnt fuse, and the bomb goes off.

• Players: 2–5 (one expert and 1–4 defusers); best with 3 or 4.
• You need: one standard 52-card deck, no jokers.

Defuse! is a new game written for this site and has not been playtested yet. The idea – one player knows everything but may not say it, the others have to act – is borrowed from cooperative games such as Hanabi and the video game Keep Talking and Nobody Explodes; the rules are our own. If something feels off at your table, adjust the levels (see "Levels") and let us know.

The cards

Sort the deck into three groups:

Ranks don't matter in this game – only suits and colours do (♥ ♦ are red, ♠ ♣ are black).

Setup

1. Choose the level (start with level 1) and the expert – the player who shuffles the code cards. After each bomb the role passes to the left.
2. Build the bomb. The expert shuffles the code cards for this level face down (see the table below) and lays the wires face down in a row in the middle, from the defusers' left to right: wire 1, wire 2, … Any code cards not needed are put aside face down without being looked at by the defusers.
3. The expert secretly looks at all wires and puts them back face down in the same places. The expert may look at them again at any time.
4. The expert takes the four Kings into their hand.
5. Shuffle the 40 tools. Deal the defusers 8 cards in total: 1 defuser gets 8, 2 defusers get 4 each, 3 get 3 each, 4 get 2 each. The defusers lay their cards face up in front of them – everybody may see them.
6. Count off the fuse: as many tools as the level says, in a face-down pile next to the bomb. The rest of the tools go back in the box.

Know your bomb. Everybody knows which code cards were used. At level 1 each suit appears exactly once on the bomb. At levels 2 and 3 each suit appears at most twice. At level 4 each suit appears exactly twice. This is what makes the puzzle solvable. Level 1 can be solved with upright Kings alone, without any deduction – use it to learn the hints.

Why these fuses? A fuse card burns every turn, so the fuse must last for every cut plus every spark you can survive, with a turn or two to spare for waiting. At level 4, 8 cuts and 4 sparks already take 12 turns – the fuse of 14 leaves two turns for waiting.

Talking

• The defusers may talk freely with each other – plan, argue, count.
• The expert must stay silent: no words, no sounds, no nodding, no pointing, no faces. The expert speaks only through the Kings.
• The defusers may also talk about the rules and whose turn it is. The expert stays silent even then – settle rules questions before the bomb is built.

Playing a turn

Each turn has three steps.

1. Hint (optional). The expert may lay one King from their hand face up next to any wire that hasn't been cut yet:

• King upright below the wire: "this wire is exactly this suit". (K♠ upright = the wire is a spade.)
• King crosswise below the wire: "this wire is this colour". (K♠ crosswise = the wire is black: ♠ or ♣.)

A hint must be true. Each King can be used only once and stays on the table, so everyone can see the hints. The expert may also give no hint and keep the Kings for later.

2. Cut or wait. The defusers agree on one of the following:

• Cut: one defuser lays one of their cards face up on the leftmost wire that is still uncut. Wires must be cut in order – you may not skip one.
• Wait: nobody cuts this turn (for example because you don't hold a suit that could be right).

3. Check and draw.

• Right suit – the wire is cut. The expert turns the code card face up and lays the defuser's card on top of it. The next wire is now the leftmost one.
• Wrong suit – spark! The card is laid face up above that wire. It stays uncut, and everybody now knows one suit it is not. Count the sparks: if this was the spark at which the bomb goes off (see the level table), you lose.
• Then the fuse burns: the defuser who cut (after a wait, any defuser) takes the top card of the fuse into their hand, face up.

Example of a cut: The first wire is the A♥. Ben cuts it with the 6♣ – spark. The 6♣ goes above wire 1: it's not a club. Next turn Carla cuts with the 8♥: right suit. The expert turns up the A♥ and puts the 8♥ on it.

End of the game

• You win as soon as the last wire is cut.
• You lose if the bomb goes off – at the spark named for your level, or when the last fuse card has been taken and a wire is still uncut.

After a win, go up one level with a new expert. After a loss, try the same level again. Getting through level 4 is a real achievement.

Worked example

Level 1, three players: Anna is the expert, Ben and Carla are defusers. The bomb is, from left to right, A♦ A♠ A♥ A♣ – only Anna knows that. Ben holds 4♥ 7♠ 9♦ J♣, Carla holds 3♠ 5♣ 8♥ Q♦. The fuse has 8 cards.

1. Turn 1. Anna lays K♠ upright below wire 2: wire 2 is a spade. So wire 1 isn't. Ben and Carla guess hearts for wire 1: Ben cuts with 4♥ – spark (1). The 4♥ goes above wire 1. Ben takes a fuse card (7 left).
2. Turn 2. Anna lays K♦ crosswise below wire 1: it's red. Not hearts, so it must be diamonds. Carla cuts with Q♦ – cut! Anna shows the A♦. Carla takes a fuse card (6 left).
3. Turn 3. No hint needed: wire 2 is a spade. Carla cuts with 3♠ – cut (5 left).
4. Turn 4. Wires 3 and 4 must be hearts and clubs, but in which order? Anna lays K♣ upright below wire 4. So wire 3 is hearts: Carla cuts with 8♥ – cut (4 left).
5. Turn 5. Ben cuts wire 4 with J♣ – defused! One spark, one King to spare.

Tips for beginners

• Count suits. At level 1 a suit that's already cut can't come again. At level 4 each suit comes exactly twice – keep track.
• Hints on later wires count too. "Wire 3 is a spade" also tells you something about wires 1 and 2.
• Expert: look at the defusers' cards. A hint for a suit nobody holds only helps if they can wait for it.
• Save a King for the end. The last two wires are often a 50-50 guess.
• Crosswise when the right King is gone. A crosswise King needn't match the wire: K♣ crosswise under a spade wire says "black". That pays at levels 2–4, when a suit appears twice and its own King is already on the table.
• Waiting is not free – the fuse burns anyway. Wait only if you really have no sensible card.

Variants

All optional – agree before you start.

• Sand timer: instead of the fuse, set a timer (e.g. 2 minutes, 3 at level 4). Defusers draw from the unused tools. When time is up, the bomb goes off.
• Safety pin: shuffle one joker into the tools. It cuts any wire correctly.
• Silent defusers: the defusers may not talk either – each decides alone whether to cut. Much harder.
• Hard mode: the expert gets only three Kings (the player on the expert's left removes one unseen).