This guide is for strategy tips: How to interpret clues, how to give clues, how to decide to play, discard or clue.

General

On BGA, there is no 1-strategy-to-be-played. However, if people start playing different strategies in 1 game, the game is doomed to fail. That is why communication in advance is very important, and why most hanabi-players get a lot of red thumbs. (Different strategy is interpreted as ruining the game.)

Basics

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, making the total number of clues in the entire game 25, 21, or 18. 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 PLAY LATER), or
   b) a useful card to be played (interpret it as PLAY NOW).

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 get a clue that marks multiple cards, and you can identify it is in fact a clue for play (see Basic Rule 1), you should play the newest (left-most) card. If an older card was "the playable card", it would probably be clued earlier. The logical conclusion must be, that the newest card, was the card you all have been waiting for, and you happened to draw it.

Basic Rule #3 (playing).

   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 Example

Imagine the following starting situation:

           (oldest ... newest)
 Player 1:  W1, Y1, B2, Y2, B2
 Player 2:  G1, G1, W3, Y2, B1
 Player 3:  B1, R4, W4, R3, G3

P1 can clue 1s to P2. But that will mark both G1's, so it's not the best option. Better is for P1 to clue P3 1s, or blue. (If BLUE-clue is given, then P3 will not worry about the B1 in P2'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 P3's hand.)

P2 will clue 1s to P1. He knows that P3 prefers to play his 1. And P2 is the only person who can see that the 1s in both P1's hand, and P3'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. P1 clues BLUE to P3 (7 clues).

2. P2 clues 1 to P1 (6 clues).

3. P3 plays B1 and draws R1.

4. P1 plays W1 and draws G4.

The game now looks like this, with P2 to move:

           (oldest ... newest)
 Player 1:  G4, Y(1), B2, Y2, B2                   Played: R0, Y0, G0, B1, W1
 Player 2:  G1, G1, W3, Y2, B1
 Player 3:  R1, R4, W4, R3, G3                     Discarded: -

5. P2 clues RED to P3.

There are two possible continuations from here. Option 1

6. P3 plays R1 and draws Y5.

7. P1 plays Y1 and draws Y3.

8. P2 discards B1 and draws G2 (7 clues).

9. P3 clues 1 to P2 (6 clues).

10. P1 discards B2 and draws R4 (7 clues).

11. P2 plays G1 and draws B5.

12. P3 clues 2 to P2 (6 clues).

And the game will look like this, with P1 to move:

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

Option 2

6. P3 clues 1 to P2 (5 clues). This move delays him playing the R1, but will make P2 more confident in discarding since he knows all the useless 1s.

7. P1 plays Y1 and draws Y5.

8. P2 plays G1 and draws Y3.

9. P3 plays R1 and draws G2.

10. P1 discards B2 and draws R4 (6 clues).

11. P2 discards B1 and draws B5 (7 clues).

12. P3 clues 2 to P2 (6 clues).

And the game will look like this, with P1 to move:

           (oldest ... newest)
 Player 1:  R4, Y5, G4, B(2), Y(2)                Played: R1, Y1, G1, B1, W1
 Player 2:  Y3, G(1), W3, Y2, B(1)
 Player 3:  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 P1, 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

[to be added...]