Tips hanabi

General

On BGA, there is no 1 set strategy (convention) to be played. However, if people start playing different conventions in one game, the game is doomed to fail. It is a good idea to discuss before the game which conventions you will be using.

The strategies explained in this guide all have 1 goal in mind: to get the highest possible score, in the most amount of games. There are people who find score less important, and want to challenge themselves logically, or "just want to have fun". Again, communication in advance of the game is key.

Imagine this 'ideal' game. You play with 3 players and reach the maximum score of 25 points (5-colour game). At the end, there will be (at least) 12 cards left in the hands of the players, (at least) 1 clue token available and 25 cards will have been played. This means, that from the 50 cards of the deck, (50 - 25 - 12 =) 13 cards have been discarded and converted into clue tokens. You get 8 clue tokens at the start, and you will have gotten a 5 clue tokens from playing the 5s. This means that in the entire game, there were 13 (discards) + 8 (start) + 5 (completing a colour) - 1 (token left at the end) = 25 clue tokens available for playing.

On average, this means 1 clue token per 1 playable card. No matter what variant you play, you will end up with roughly this number. (Worst: 5-player game, with players that have 4 cards in their hands, playing 5 colours. This gives 22 tokens for 25 cards = 0.88 clue token per card. Best: 2-player game, with players that have 6 cards in their hands, playing 6 colours. This gives 35 tokens for 30 cards = 1.17 token per card.)

The strategies below are based on an optimization of economical use of the clue-tokens. The strategies below are only the basic elements of the convention generally played at BGA. By combining them and using some logical extrapolations one can derive moves which are even more advanced. There are also groups of players on BGA and elsewhere who play with quite different convention sets, where each set has its advantages and downsides.

Basics

Before all other rules, every player must look at what cards they can see, and deduce what cards in a clue must be or cannot possibly be. Blindly following the other basic rules without checking for impossible cards will result in mistakes. This is critically important with the played and discarded cards, because everybody can see the same things, and so people will gives clues knowing that you have this information. For example: if the played red stack is up to 3, and there is a red 2 in the discard pile, then you know that you cannot be holding a red 2, so when somebody gives you a clue of 2s, you should read it as "these cards are 2s which are not red" and think about whether that changes the way you interpret the clue. If you can narrow it down to one or two cards, the clue might mean something other than PLAY NOW.

This leads to Basic Rule #0 (thinking).

   After you receive a clue, look for every visible card of that type.
   Before following other rules, think about whether this changes the meaning.

If there isn't an obvious meaning to the clue, then continue. It is unlikely to be anything complicated.

The basic game, plays with 50 cards: 10 for each colour. If you want to get the maximum score of 25 points, you need to play 25 cards. Some of the cards are left in the players hands at the end of the game. Depending on the number of players, this will be 8, 12, 12, or 15 (for 2p, 3p, 4p, and 5p respectively). This means in the entire game, there are 17, 13, or 10 cards that can be discarded for clues. You also get 8 clue tokens at the start and 4 useable clues from suite completion, making the total number of clues in the entire game 29, 25, or 22. This gives the logical conclusion that you can not clue the colour AND number for every card in your hand, because there are simply not enough clues.

It is therefore paramount, that only useful cards are clued. If you mark a card that you know will not be played, it will cost another clue (-1) to make your team mate discard that card to gain a clue (+1), which is a net result of 0. If the card is not marked, your team mate will discard it eventually to gain a clue (+1), which is a net result of +1.

This leads to Basic Rule #1 (cluing).

Every card that is marked, is either

   a) (a) useful card(s) to be saved (interpret it as HOLD TO PLAY LATER), or
   b) a useful card to be played (interpret it as PLAY NOW).
   Therefore: NEVER mark useless cards

Most hanabi-players on BGA play by this main rule. So when a clue is given, ask yourself "Is this clue to save something"? If not, it is to get played. Saving cards is important because there are only 2 cards of value 2, 3, and 4 in each suit, and only 1 card of value 5. To not get stuck on that colour it is urgent to keep the last copy of a card safe (prevent from discarding it).

The game interface puts every new card you draw, on the left-hand side of your hand. This means, the left-most card is the newest card, which makes your right-most card automatically the oldest. If a card has been in your hand for a long time, and you have not been given a clue that marks it, it is logical that it is a useless card and safe to discard.

Hence, Basic Rule #2 (discarding).

   Discard first what you know is useless (like a clued 1 when all 1s are already played).
   After that: discard your oldest (right-most) unclued card.

Note, that this rule is already a bit tricky. At the start of the game, every card can be considered equally old. This is where personal preference of players starts to matter.

Another result from the newest --> oldest order, is the interpretation of multiple marked cards. When you haven’t been clued a certain kind of clue (call it "X"), while there were tokens, and right after you draw a card, you receive a "X" clue on multiple cards including the newest and you can identify it as a play clue (see Basic Rule 1), you can logically deduce that the newest (left-most) card is the one to play. If an older card was "the playable card", it would probably have been clued earlier – provided you can identify your teammates did have the opportunity to give the same clue earlier. The logical conclusion must be that the card in the leftmost slot was the card your team have been waiting for (the "wait factor"), and you happened to draw it.

Basic Rule #3 (playing).

   If the wait factor is validated, play the newer (left-most) clued card

So most people on BGA expect you to ONLY play the clued card on the left. The rest of the cards are just to be kept on your hand. Beware that there are different approaches and not all players play by this convention.

Basic Rule #4 (triggering end of game).

Once all cards have been drawn, each player has one more play, including the player who drew the last card. Therefore, it is often useful to delay the end of game by giving worthless or low-value clues instead of discarding.

Basic Example

Imagine the following starting situation:

           (newest ... oldest)
 Alice:  W1, Y1, B2, Y2, B2
 Barry:  G1, G1, W3, Y2, B1
 Carla:  B1, R4, W4, R3, G3

Alice can clue 1s to Barry. But that will mark both G1's, so it's not the best option. Better is for Alice to clue Carla 1s, or blue. (If BLUE-clue is given, then Carla will not worry about the B1 in Barry's hand that is about to be discarded. Both 1-clue or BLUE-clue only mark 1 card, so give equal information about the other cards in Carla's hand.)

Barry will clue 1s to Alice. He knows that Carla prefers to play her 1. And Barry is the only person who can see that the 1s in both Alice's hand, and Carla's hand are different.

Everyone will have to wait for B2 to be discarded, before the second B2 can be clued. Everyone will also have to wait for G1 to be discarded, before the second G1 can be clued. Alternatively, when R1 is drawn and clued, then both G1's may be clued, since all 1's will be played and all cards marked 1 can be safely discarded.

So, the first four moves are:

1. Alice clues BLUE to Carla (7 clue-tokens).

2. Barry clues 1 to Alice (6 clue-tokens).

3. Carla plays B1 and draws R1.

4. Alice plays W1 and draws G4.

The game now looks like this, with Barry to move:

           (newest ... oldest)
 Alice:  G4, Y(1), B2, Y2, B2                   Played: R0, Y0, G0, B1, W1
 Barry:  G1, G1, W3, Y2, B1
 Carla:  R1, R4, W4, R3, G3                     Discarded: -

5. Barry clues RED to Carla.

There are two possible continuations from here. Option 1

6. Carla plays R1 and draws Y5.

7. Alice plays Y1 and draws Y3.

8. Barry discards B1 and draws G2 (7 clues).

9. Carla clues 1 to Barry (6 clues).

10. Alice discards B2 and draws R4 (7 clues).

11. Barry plays G1 and draws B5.

12. Carla clues 2 to Alice (6 clues).

And the game will look like this, with Alice to move:

           (newest ... oldest)
 Alice:  R4, Y3, G4, B(2), Y(2)                Played: R1, Y1, G1, B1, W1
 Barry:  B5, G2, G(1), W3, Y2
 Carla:  Y5, (R)4, W4, (R)3, G3                Discarded: B1, B2

Option 2

6. Carla clues 1 to Barry (5 clues). This move delays him playing the R1, but will make Barry more confident in discarding since he knows all the useless 1s.

7. Alice plays Y1 and draws Y5.

8. Barry plays G1 in slot 2 and draws Y3.

9. Carla plays R1 and draws G2.

10. Alice discards B2 and draws R4 (6 clues).

11. Barry discards B1 and draws B5 (7 clues).

12. Carla clues 2 to Alice (6 clues).

And the game will look like this, with Alice to move:

           (newest ... oldest)
 Alice:  R4, Y5, G4, B(2), Y(2)                Played: R1, Y1, G1, B1, W1
 Barry:  B5, Y3, G(1), W3, Y2
 Carla:  G2, (R)4, W4, (R)3, G3                Discarded: B2, B1

Both options are equally valid. They end up in the same situation, with only the cards in hands being in a different order. Since the cards are picked at random, there is no valid reason to say one option is better than the other.

In both options, the 2-clue is given to Alice, to mark both 2s as playable. Since all 1s are played, all 2s will be playable. Note that, in this game, two 1s where marked with one clue (and played); and two 2s were marked with one clue (and will be played). As stated in the beginning, there are a total of 21 clues (in this variant) to mark 25 cards. At this point in the game, there are 16 clues left to mark 18 cards. With only two more "efficient" clues, the game can end with a perfect score.

Advanced Moves

Play refusal

Sometimes you have a card to play but the next player’s chop card is critical and you have no tokens to tell them. So the only option you have is to discard your CHOP card, even when you know you have a playable card. This is a risky move, since your team mate(s) might expect you to play, instead of discard. (always try to give them a clue token to use or help them play their hand as fast as possible). So the next player will think "if s-he had played I would have been forced to discard, since there were no tokens, so s-he doesn’t want me to discard, so I should keep my chop card."

Positional Discard

Sometimes at the end of the game you will have no useful cards to play. You want to give a clue, but you have no remaining clue-tokens. In this case, you can discard the card in the same position as the card that you want that player to play.

Example Positional Discard

All players have agreed on the convention that a colour-clue means PLAY the left-most marked card.

           (newest ... oldest)
 Player 1:  XX, XX, XX, XX, XX                   Played: R5, Y5, G4, B5, W5
 Player 2:  ??, ??, ??, ??, ?3
 Player 3:  G5, B2, R4, B3, W1                   Discarded: -

In this example, when there are no clue-tokens left, Player 2 can discard their DRAW, to indicate to Player 3 the position of the last remaining playable card.

Hint to Discard

You can hint a player to discard specific cards in order to save multiple cards, to save cards without causing a confusion about finesse/reverse.

Example Hint to Discard In this example, all 1s have been played already. Both the Y3 and the G4 need to be saved.

 Player 1: G1, R1, B4, Y3, G4

If Player 1 is given a 4-clue, the G4 will be saved, but the Y3 will be the new CHOP card. One option to save both Y3, and G4 is to give Player 1, a 1-clue. This would make the R1 the new CHOP card, and the G1 will be the next CHOP card.

Alternatively, you can give an empty clue to get the clued player to save two CHOP cards.

Double Save

This is an alternative solution if you are low on clue-tokens, or don't have enough players to execute multiple saves in a row.

Example Double Save In this example, W1 has not been played yet. Both the Y3 and the G4 need to be saved.

 Player 1: G1, R1, B4, Y3, G4

This situation is similar as the Hint to Discard. However, in this situation a 1-clue will be interpreted as PLAY G1 (which isn't playable). To save both Y3 and G4, an empty clue can be given to Player 1 (either 2 or 5 or white in this situation). This will cause them to wonder why you would be wasting a clue to give no information, and find out it must be because cluing normally would enable you to save one CHOP card, not two. So it costs 1 clue-token for 2 saves, but gives you no information about the saved cards.

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2P GAMES
With 2 players, you are limited in your options. Therefore the gameplay is different from 3+P games.

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3+P GAMES

Prompt

A prompt can clarify (an) already marked card(s) to be played as well as mark the next card to play.

Example Prompt

           (newest ... oldest)
 Alice:  XX, XX, XX, XX, XX                   Played: R0, Y1, G0, B2, W0
 Barry:  ??, ??, ??, ?2, ?5
 Carla:  Y3, G5, R4, B3, W1                   Discarded: -

Alice gives a yellow-clue to Carla, marking Y3 as PLAY. Barry sees that the Y3 is ALMOST playable. This means that Barry has the LOGICAL in-between step: Barry has to play Y2. In this case, the Y2 is not on the DRAW card. The logical place for that card is the already marked 2. So Barry can assume that his card between his CHOP and the 5 is the Y2.

Finesse

This advanced move, can get you 2 cards into play, with only 1 clue-token. You do this, by marking an ALMOST playable card as playable. Someone else will have to play the LOGICAL in-between step, to make the card genuinely playable.

Example Finesse (#1)

           (newest ... oldest)
 Alice: ??, ??, ??, ??, ??                   Played: R0, Y0, G0, B0, W0
 Barry:  ??, ??, ??, ??, ?5
 Carla:  G5, B2, R4, R3, W1                   Discarded: -

Alice gives a blue-clue to Carla, marking B2 as PLAY. Barry sees that the B2 is ALMOST playable. This means that Barry has the LOGICAL inbetween step: Barry has to play B1. The only logical place for that card is at the LEFT-MOST POSITION so Barry can assume that the DRAW card is the playable B1. If it was somewhere else in your hand, the card would have been clued earlier. Note: for the in-between player, a prompt always has priority over a finesse; if a player has a marked card that can be the in-between card, they should play it.

Example Finesse (#2)

           (newest ... oldest)
 Alice:  ??, ??, ??, ??, ??                   Played: R0, Y1, G2, B0, W1
 Barry:  Y2, R1, R1, G5, W5
 Carla:  XX, XX, R2, XX, XX                   Discarded: G4, R3

Alice gives a 5-clue to Barry, saving W5 and G5 from being discarded. Barry sees nothing of interest in the hand of Carla, so discards his CHOP (R1) and draws R4. Carla gives a setup for Alice by marking Y2 with a yellow-clue. The game now looks like this:

           (newest ... oldest)
 Alice:  ??, ??, ??, ??, ??                   Played: R0, Y1, G2, B0, W1
 Barry:  R4,*Y2, R1, G5*,W5*
 Carla:  XX, XX, R2, XX, XX                   Discarded: G4, R3, R1

Alice can't give a red-clue to Barry, because this would cause Barry to bomb with r4. Instead, Alice now gives a red-clue to Carla, marking R2 as PLAY. Barry sees that the R2 is ALMOST playable. This means that Barry has the LOGICAL inbetween step: Barry has to play R1. Barry knows that R1 can only be at the DRAW position, or at the middle position. Since Alice deliberately let Barry discard a playable R1 the round before, Barry concludes that she was already holding a second R1 at the time. Therefore, the LOGICAL place for the R1 to be, is at the middle position; NOT the DRAW position.

Bluff

This works the same as finesse. Only this time, the LOGICAL inbetween step, is a different playable card, so the player is tricked. It is slightly less strong that finesse, because it gives 1 play + 1 save for 1 clue-token.

Example Bluff

           (newest ... oldest)
 Alice:  XX, XX, XX, XX, XX                   Played: R0, Y3, G1, B1, W0
 Barry:  W1, B3, R4, B2, G5
 Carla:  ??, ??, R?, ??, ??                   Discarded: -

Alice gives a red-clue to Carla, marking it as PLAY. Barry sees that the R2 is ALMOST playable, so applies finesse logic and plays his DRAW card. Much to Barry's surprise, he has not played R1, but W1 (which was also playable). Because Carla saw Barry playing his DRAW, which was a different colour than the clue he received, Carla knows it was a bluffed finesse situation. She concludes that her red card is R2, and saves it for later.

Reverse

This works the same as finesse. Only this time, the LOGICAL inbetween step, is a different players hand. This also gets 2 plays for 1 clue-token, but takes longer than a normal finesse.

Example Reverse

           (newest ... oldest)
 Alice:  XX, XX, XX, XX, XX                   Played: R2, Y0, G2, B1, W0
 Barry:  ??, ??, W?, G3, ??
 Carla:  W1, B2, R4, B3, G5                   Discarded: -

Alice gives a white-clue to Barry, marking it as PLAY. However, Barry sees that the DRAW card of Carla is a playable card of the same colour. Therefore, Barry may assume that it is (reversed) finesse, and that his white MIGHT be W2, nearly playable. Barry decides to then first play his G3, which is a safer option for the moment, and see how Carla reacts. Carla recognises the (reversed) finesse play, and plays her DRAW card to play the W1.

Having the optimal player draw the last card (endgame)

At the end of the game, the person who draws the last card (which happens either by playing or discarding) triggers the end of the game. After the last card is drawn, each player receives exactly one more turn. Sometimes near the end of the game you will want a specific player to play or discard in order to get the last turn. Giving an unusable clue can prevent a player from drawing the last card and begin the last round.

Table:
1 card remaining in deck - Your turn
R Y G B W M
5 5 3 4 5 5

XX|XX|B5 - me

??|??|?3 - you

Y1|G4|G5 - 3rd player

In this situation, assume everyone knows where the remaining playable cards are. Instead of discarding in this situation, you want the 3rd player be the one to play and draw the last card. Give any clue to prevent triggering the endgame so that 3rd player can play G4 triggering the endgame and then in their last turn play the G5.

Strategies for 2-Player games

Strategy #1

Pro's: Easy to execute
Con's: Double discard possible for 4s. Easy to get the hands locked.

Guidelines
1. Number-clue means “save all the cards that were marked by this clue”. Try to give save-clues as late as possible.

2. Non-unique 2s and 3s must be saved as much as possible. (Try to avoid double saves if possible.) Uniques should always be saved.

3. Colour-clues mean “play the newest card that was marked by this clue”. Other cards that are marked by the clue may be discarded when not previously marked by a number-clue.

4. If more than 5 clue-tokens are available, discarding unknown cards should be avoided, but known useless cards may be discarded freely.

5. If there are less than 2 clue-tokens available, colour-clues may be given only a. If it leads to two or more plays in a row. b. If the playable card is on CHOP.

6. A colour-clue may re-mark a card that’s already marked by a number if: a. It also marks a previously unmarked card that is playable. (Either immediately, or immediately after playing the card that was marked with a number.) b. As a stall-clue (see 7).

7. When just 2 of the hand-slots are filled with non-saved cards, that player should try to avoid discarding two turns in a row (including the turn after the save-clue that leads to this state).

8. If a clue is given while avoiding discarding twice in a row: guideline 4 no longer applies; also stall clues may be given: a. A colour-clue that re-marks a saved card, without marking an unmarked card. For example to indicate an accidental double save, or to clarify a playable card. b. An empty-clue: a clue that marks none of the cards. This can be used to convey information on multiple playable cards. c. A 5-clue. If 5a and 5b are not possible, a re-clue on the 5s is allowed.

9. Nearing the end of the game, when the number of saved cards in all the hands + the number of cards in the deck is equal to the number of card that need to be played to get the maximum (possible) score, discarding should be avoided as much as possible - so stall clues may be given, non-unique 4s may be saved, etc.

Strategy #2

Pro's: Guarantees a score of 28+
Con's: Easy to get the hands locked.

Guidelines
The game is divided into three stages:

 1. The Early game: The first 3 or 4 moves of the game.
 2. The Mid game: Everything that's not early or late game.
 3. The End game: The last moves, starting from the point where the number of "saved cards" + deck = maximum achievable score.

Early game
In the early game, the goal is to 'sort' the hand cards into "old" cards and "new" cards. Since all cards are equally old in the beginning, it is unclear which cards are relevant, and which aren't. In order to do so, players follow these guidelines:

1. Players are not allowed to discard before 3 clue-tokens are spent.

2. After the early game, the right-most unclued cards will be considered "old" and therefore discardable. So the focus of the clues in the early game should be to save the valuable three right-most cards.

3. 1s should be marked with colour as much as possible.

4. A 1-clue should only be given when it marks three or more unique 1s.

5. 4-clues should only be given, when the 4 is blocking a colour-clue in the future. Cards marked with 4 in the early game should be discarded in the mid game.

Mid game
In the mid game, the goal is to play as many playable cards as possible, and save as many useful cards as possible. In order to do so, players follow these guidelines:

1. Players will be as efficient as possible with clue-tokens. Re-marking cards (spending a clue-token that gives MORE information on a saved card) is highly discouraged.

2. All 2s, 3s and 5s must be saved, even when the 2s or 3s are not unique.

3a. Any clue means "play the newest, PREVIOUSLY UNMARKED, card". With the exception of a SAVE-clue, or a correction-clue.

3b. A card can be saved in four possible ways:

I. A number-clue that marks the CHOP card.
II. A colour-clue that marks a PLAY card, and in addition marks another card of the same colour.
  This other card is saved. 
III. A SCREAM discard. When player 1 can play a card, but chooses to discard instead, it is called a SCREAM discard.
  This signals to player 2 that their CHOP card must be saved.
  It is recommended that player 2 spends the token, in case they have a long chain of cards that need saving.
IV. A deliberate misplay. When player 1 gives player 2 a PLAY-clue, that causes player 2 to BOMB.
  Player 2 knows to SAVE all the cards OLDER than the card that was used to bomb.

3c. When a useless card is marked as SAVE, it is desired to give a correction-clue. This re-marks the card, indicating its uselessness. Preferably, this shouldn't mark any other cards. When it does, the clue is a PLAY-clue with the correction as an additional benefit.

4. Double discarding (discarding a card that could be the same card that was just discarded), is not allowed.

5. Play-clues shouldn't be given when there are 3 or less clue-tokens available, except when it leads to more than 1 PLAY.

6. When a player has only two unmarked cards in their hand (all other slots are filled with SAVES), then this player should keep discarding to a minimum.

7. When a player has only one unmarked card in their hand, then this player is forbidden to discard two turns in a row.

End game
In the end game, the goal is to get the last remaining cards sorted in the correct hands, to maximise the score. This is achieved, by following these guidelines:

1. Discarding is highly discouraged. If there are enough clue-tokens, then stall-clues should be given.

2. Playable cards must be prioritised based on the number of plays it unlocks. This way the number of SAVED cards in hands is minimised.

3. It is recommended that both players keep at least one 5 in their hand. This way, in the last turn, both players can make a final move.