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User:Sammy McSam/Hanabi
⚠ Work in progress ⚠ Contains logic
Resources
Guides
- Definitions
- Tips_hanabi
- Reference for BGA by Romain672
- Tips for end game by Romain672
- Hanabi conventions by Postmans
- Conventions et Techniques by Blacktango
Discussion
Tools
Interpretation
In order to play cooperatively, we need to mark playable cards to get them to play at the correct time. To maximise cooperation, we need to be able to predict the possible moves of other players. The cost of being able to predict moves is to limit the number of moves
- If a card is playable, logically we assume it will be marked by a clue before it is discarded (unless there is another copy visible).
| Situation | Response | Receiver's Interpretation | Clue type | ||
|---|---|---|---|---|---|
| Alice clues 2 to Cathy:
blue5black powderblue1,with a 1clue,black powder Bob 🡲 card back2,with a 2clue,card backcard backcard back Cathy 🡲 |
Bob plays blue1,with a 1clue, | connects to card back2,with a 2clue, | 🟰 | blue2,with a 2clue,card backcard backcard back Cathy 🡲 | Prompt:
|
| Alice clues 2 to Cathy:
blue1blue5black powderblack powder Bob 🡲 card back2,with a 2clue,card backcard backcard back Cathy 🡲 |
Bob plays blue1 | connects to card back2,with a 2clue, | 🟰 | blue2,with a 2clue,card backcard backcard back Cathy 🡲 | Finesse:
|
| Alice clues b to Cathy:
blue1blue5black powderblack powder Bob 🡲 card back2,with a clue,card backcard backcard back Cathy 🡲 |
Bob plays red1 | as blue1 | 🟰 | blue2,with a blueclue,card backcard backcard back Cathy 🡲 | Bluff:
⚠ All bluff targets must be one card away from playable |
| Alice clues 3 to Donald:
red1blue5black powderblack powder Bob 🡲 blue2,with a blueclue,black powderblack powderblack powder Cathy 🡲 card back3,with a 3clue,card backcard backcard back Donald 🡲 |
Bob plays blue1 | connects to card back3,with a 3clue, | ➕blue2 Cathy🟰 | blue3,with a 3clue,card backcard backcard back Donald 🡲 | Long Finesse:
|
| Cathy plays blue2 | connects to blue3,with a 3clue, | 🟰 | blue3,with a 3clue,card backcard backcard back Donald 🡲 | ||
| Alice clues 3 to Donald:
blue5black powderblue1black powder Bob 🡲 blue2black powderblack powderblack powder Cathy 🡲 card back3,with a 3clue,card backcard backcard back Donald 🡲 |
Bob plays blue1 | connects to card back3,with a 3clue, | 🟰 | blue3,with a 3clue,blue2card backcard back Donald 🡲 | Prompt + Finesse:
|
| Cathy plays red1 | as blue2 | ➖ blue2 🟰 | blue3,with a 3clue,card backcard backcard back Donald 🡲 | ||
| Alice clues 3 to Donald:
blue5black powderblue1,with a 1clue,black powder Bob 🡲 red1black powderblack powderblack powder Cathy 🡲 card back3,with a 3clue,card backcard backcard back Donald 🡲 |
Bob plays blue1,with a 1clue, | connects to card back3,with a 3clue, | 🟰 | blue3,with a 3clue,blue2card backcard back Donald 🡲 | Prompt + Bluff:
⚠ This clue type is dangerous because Bob may not cooperate and try to bluff red1 himself before responding to blue3,with a 3clue,. |
| Cathy plays red1 | as blue2 | ➖ blue2 🟰 | blue3,with a 3clue,card backcard backcard back Donald 🡲 | ||
| Alice clues 3 to Donald:
blue1blue5black powderblack powder Bob 🡲 red1black powderblack powderblack powder Cathy 🡲 card back3,with a 3clue,card backcard backcard back Donald 🡲 |
Bob plays blue1 | connects to card back3,with a 3clue, | 🟰 | blue3,with a 3clue,blue2card backcard back Donald 🡲 | Finesse + Bluff:
|
| Cathy plays red1 | as blue2 | ➖ blue2 🟰 | blue3,with a 3clue,card backcard backcard back Donald 🡲 | ||
| Alice clues b to Donald:
red1blue5black powderblack powder Bob 🡲 blue2black powderblack powderblack powder Cathy 🡲 card back3,with a clue,card backcard backcard back Donald 🡲 |
Bob plays red1 | as blue1 | ➕blue2 Cathy🟰 | blue3,with a blueclue,card backcard backcard back Donald 🡲 | Promise Bluff:
|
| Alice clues 4 to Emily:
blue1blue5black powderblack powder Bob 🡲 blue2black powderblack powderblack powder Cathy 🡲 red1black powderblack powderblack powder Donald 🡲 card back4,with a 4clue,card backcard backcard back Emily 🡲 |
Bob plays blue1 | connects to card back4,with a 4clue, | ➕blue2 Cathy🟰 | blue4,with a 4clue,blue3card backcard back Emily 🡲 | Long Finesse + Bluff:
|
| Cathy plays blue2 | connects to blue4,with a 4clue, | 🟰 | blue4,with a 4clue,blue3card backcard back Emily 🡲 | ||
| Donald plays red1 | as blue3 | ➖ blue3 🟰 | blue4,with a 4clue,card backcard backcard back Emily 🡲 | ||
| Alice clues 4 to Donald:
blue1blue5black powderblack powder Bob 🡲 red1black powderblack powderblack powder Cathy 🡲 card back4,with a 4clue,card backcard backcard back Donald 🡲 |
Bob plays blue1 | connects to card back4,with a 4clue, | 🟰 | blue4,with a 4clue,blue2blue3card back Donald 🡲 | Finesse + Promise Bluff:
|
| Cathy plays red1 | as blue2 | ➖ blue2 🟰 | blue4,with a 4clue,blue3card backcard back Donald 🡲 | ||
| Alice clues 2 to Donald:
blue1blue5black powderblack powder Bob 🡲 red1black powderblack powderblack powder Cathy 🡲 card back2,with a 2clue,card backcard backcard back Donald 🡲 |
Bob plays blue1 | connects to card back2,with a 2clue, | 🟰 | blue2,with a 2clue,card backcard backcard back Cathy 🡲 | Double Bluff:
|
| Cathy plays red1 | as blue2 | ➖ blue2 🟰 | card2,with a 2clue,card backcard backcard back Cathy 🡲 | ||
Extraction
It is possible to extract a card that is 'blocked' by an unplayable card using two clues.
- Clue the target with colour.
- Clue the target with number.
white5yellow4red3green5 Bob 🡲 white4green4multicolour2yellow2 Cathy 🡲
- Avalanche of colors option is on, so multicolour cards are marked by any colour clue.
- Cathy's yellow2 should play before it is discarded.
- The focus of a 2 clue on its own will be multicolour2 and the focus of a yellow clue will also be multicolour2.
- Alice to Cathy: these 2 cards are yellow.
red yellow1 green blue white multicolour white5yellow4red3green5 Bob 🡲 white4green4multicolour2,with a 1clue,yellow2,with a yellowclue, Cathy 🡲
- Bob to Cathy: these 2 cards are 2s - this fix clue changes the focus from the left 2 to the other 2.
red yellow1 green blue white multicolour white5yellow4red3green5 Bob 🡲 white4green4multicolour2,with a 12clue,yellow2,with a yellow2clue, Cathy 🡲
- Note: if a multicolour card is the intended target of a play clue, the clearest clue would be a colour that does not splash any other card.
- extract white2:
- Alice to Cathy: these 2 cards are white.
- Focus is left.
- card back2card back3,with a clue,card backcard back2,with a clue, Cathy 🡲 red2white3,with a whiteclue,black powderwhite2,with a whiteclue, Cathy 🡲
- Bob to Cathy: these 2 cards are 2s.
- Changes focus from left to right.
- card back2,with a 2clue,card back3,with a clue,card backcard back2,with a 2clue, Cathy 🡲 red2,with a 2clue,white3,with a whiteclue,black powderwhite2,with a white2clue, Cathy 🡲
- extract white2 with avalanche:
- Alice to Cathy: these 3 cards are white.
- Focus is left.
- card back2,with a clue,card back3,with a clue,card backcard back2,with a clue, Cathy 🡲 multicolour2,with a whiteclue,white3,with a whiteclue,black powderwhite2,with a whiteclue, Cathy 🡲
- Bob to Cathy: these 2 cards are 2s.
- Changes focus from left to right.
- card back2,with a 2clue,card back3,with a clue,card backcard back2,with a 2clue, Cathy 🡲 multicolour2,with a white2clue,white3,with a whiteclue,black powderwhite2,with a white2clue, Cathy 🡲
Since black powder can't be clued with colour, extraction is a little different:
- Clue the target with number.
- Clue the card to the left of the target with colour.
- extract black powder2:
- Alice to Cathy: these 3 cards are 2s.
- Focus is left.
- card back2,with a 2clue,card back2,with a 2clue,card back2,with a 2clue,card back Cathy 🡲 yellow2,with a 2clue,red2,with a 2clue,black powder2,with a 2clue,black powder Cathy 🡲
- Bob to Cathy: this card is red.
- Changes focus from left to right.
- card back2,with a 2clue,card back2,with a 2clue,card back2,with a 2clue,card back Cathy 🡲 yellow2,with a 2clue,red2,with a red2clue,black powder2,with a 2clue,black powder Cathy 🡲
Why extraction works
- Alice gives a white colour clue to indicate to Bob that she is giving a play clue to Cathy.
- Bob has one job: don't let Cathy bomb. He sees that one of Cathy's marked white cards is playable, so he understands that he just has to help Cathy play the correct card:
- If the leftmost white card is playable, Bob does not need to do anything.
- If the leftmost white card is not playable, Bob needs to help with a follow-up fix clue.
Why colour before number?
- In each colour, only one card can be playable (two with avalanche), whereas there can be many playable cards of a certain number. So Alice singles out one colour to help Bob know her intention is for him to help Cathy play the correct card.
- A colour clue can mark a chop card without looking like a save.
How do I know it's not a finesse?
- The leftmost card may be 1-away-from-playable.
But if Bob can see that one of the cards Alice marked with colour is playable, he will prefer to give a fix clue and not blind play his finesse position.
- As Bob, consider the choice of clue:
- if Alice wanted to finesse 2b with a playable 1m in front, why skip players to give specifically a blue clue (why not another colour or number?
- if Alice wanted to finesse 4k with a playable 4r in front, why skip players to give specficially a 4 clue (why not red)?
The everlasting exception: context
Context > convention and can cause an unconventional move!
Think carefully about:
- timing (why now?),
- negative clues (e.g. "not red"),
- recently discarded cards,
- unique cards,
- tokens needed for saves or other plays
Examples
blue2,with a blueclue,multicolour1,with a multicolourclue,black powderblack powderCathy 🡲 multicolour1,with a multicolourclue,blue2,with a blueclue,black powderblack powderCathy 🡲
card backcard backcard back5,with a clue,card back5,with a clue,Bob 🡲 yellow4black powder4black powderblack powderCathy 🡲
card backcard backcard back5,with a clue,card back5,with a clue,Bob 🡲 yellow4,with a 4clue,black powder4,with a 4clue,black powderblack powderCathy 🡲
- Alice clues 4s to Cathy. How should Bob respond?
- Bob has negative 3.
- Bob had yellow2,with a yellowclue, which was marked with number 2 instead of a number 3 fix, and either:
- Bob did not discard what would have been a trash 3
- yellow4 was discarded when it could have easily been marked to prompt yellow3
In this game the context was 2.1: On move 23 a fix clue was given with number 2 instead of 3, Bob can know that their card back5,with a clue, is not yellow3 (else the fix should be 3¹, not 2). This is why it is important for each player to pay attention to how their own cards are fixed (and what cards they discard afterwards).
¹Note that there are no trash 3s at this point. If there were at least one trash 3 (e.g. white3 were played or already marked somewhere), Bob should only make this conclusion after discarding his unmarked card, to check that a 3 fix was not given due to bad touch.When is it chop focus?
Travis Hall » 16 December 2023, 01:12
When playing with high-level partners, I generally try to regard a number clue touching chop as chop-focussed unless there is a timeliness consideration.[…]when giving a finesse, we can’t wait for the discard of the chop. For example:
- Played: white2 white3black powderblack powderblack powder B 🡲 multicolour5black powderwhite4black powder4 C 🡲
A clues 4 to C. Cluing white is blocked by multicolour5. Cluing 4 can’t wait, because B will probably discard and white3 will move out of finesse. C can note the finesse response and adjust their expectation to play the left 4.
And I try to consistently clue the same way.
I recognise that many masters will clue 2s non-chop-focussed in the early game. Frankly, I’m not a fan, as this forces me to guess who does this and who does not, but I will guess because my rate of error is lower that way. I understand the consideration that 2s are the most valuable cards, but I’m not sure the risks are worth it.
Whenever somebody touches my chop with a number clue and expects me to play from the left, and I misfire, my question is always “Well, if my cards were the opposite way around, how would you have clued them?” Of the few who will answer that question at all, the answer is usually, “I would clue <number>,” and they don’t understand that this makes it impossible for me to do anything other than guess.
Since we know we can extract a playable cards with colour + number clues, it follows that number clues that mark the chop card are interpreted as:
- Unique save if the chop card can be unique
- Double discard save if the player either side of the receiver has a non-unique card of the same number
- Otherwise a left-focused play clue.
black powder1
- 1 clues that mark the chop card are interpreted as a black powder1 save (unless the receiver already has a known play).
- If a player can see black powder1, it is logical to play all cards marked 1 from oldest to newest.
The oldest is the most valuable 1 because otherwise it could have been discarded before cluing 1.
Playing a chop card marked 1 can be played because:
- black powder1 is visible (and the player who can't see it is promised black powder1)
- This player should then track the newest position that can be black powder1.
- if this card reaches chop, it should not be saved with a direct clue.
- if his card does receive a direct clue, it becomes a finesse.
- This player should then track the newest position that can be black powder1.
- a playable 1 was discarded
- a playable 1 was not bluffed
The everlasting exception: context
Context > convention and can cause an unconventional move!
Think carefully about:
- timing (why now?),
- negative clues (e.g. "not red"),
- recently discarded cards,
- unique cards,
- tokens needed for saves or other plays
Double discard avoidance saves are one of the most difficult clues to interpret because it's one of the very few times we can save non-unique cards without expecting a play response.
Nothing much is going on and there have not been any good ways to splash, give trash clues or otherwise delay one of the players.
Some players forbid a player from discarding if a double discard is possibleStrategy
Back to basics
- In a 5players player game with 4cards in hand each and avalanche, there are up to 30 possible moves per player (excluding flamboyants).
- e.g. if each hand has one avalanche multicolour card.
- In one round of play that means up to 150 possible unique positions!
- That's a lot to think about. But amazingly our human brains can filter out the vast majority of those moves as not logical given a bit of agreement on clue, play and discard interpretations (conventions).
Hand management
When to skip players
(and how to irritate them )
DDA
Efficiency 8clue tokens
Bluffs
- Bluffs are powerful...
- Easiest way to mark nice cards
Maximizing bluff opportunities
- Once we realise the power of bluffs, it follows that we want to maximise the number of bluffing opportunities available to players.
- In any given situation, it is possible to work out Alice's optimal move given the information available to her.
- The basic idea is simple: look for the bluff opportunity that is furthest ahead.
- Everyone should be making moves that enable that bluff opportunity to be used, and then work backwards from that player for the next opportunity.
So from Alice's point of view, she will see if:
- Donald can bluff Emily
- Cathy can bluff Donald
- Bob can bluff Cathy
- Alice can bluff Bob
- Donald can bluff Emily
- Cathy cannot bluff Donald
- Bob can bluff Cathy
- Alice cannot bluff Bob
Then it's quite easy:
- Alice discards
- Bob bluffs Cathy
- Cathy discards
- Donald bluffs Emily
- Donald can bluff Emily
- Cathy cannot bluff Donald
- Bob can bluff Cathy
- Alice can bluff Bob
Then it's still easy:
- Alice either double bluffs Bob & Cathy or discards
- Bob responds or bluffs Cathy
- Cathy discards
- Donald bluffs Emily
Then it's significantly more complicated for the team to predict, but not much more complex for Alice:
- Alice should probably discard (unless there is a really good bluff target available to her
- Bob makes a similar decision
- Cathy responds, double bluffs or discards
- Donald responds or bluffs Emily
When to not save unique cards
- No matter how many tokens you have, whether it is 1clue tokens or 7clue tokens, you do not always have to spend a token to save a card. Some players might find this statement controversial.
- Each player must consider the likelihood of a certain move and assess if the risk-reward of all the possible moves.
#Back_to_basics We know that there are a lot of possible moves, and even more game states.
Examples of clear good/bad
Questionable examples
Context examples
When to Trash bluff
- When you first learn about trash bluffs, you need to practice it and that's fine.
- Once you are comfortable with how it works, you need to consider if you should use a trash bluff.
- Examples where it is clearly bad
- Played: white1 blue1black powderblack powderblack powder Bob 🡲 white1,with a 1clue,white1,with a 1clue,blue2blue2 Cathy 🡲
Reverses with number white3,with a 3clue,
- Reverse finesses are often not great if the finessed card could instead be bluffed, however, it can be useful to mark a chop card as a reverse to ensure it is not discarded.
- e.g. Alice sees Bob has white2 on chop and Donald just drew white1. Normally the best moves would be for Alice and Bob to discard so that Cathy can bluff Donald's white1, but white2 is more valuable than any bluff target Alice can see, so she chooses to reverse with colour.
But what if reversing with colour would mark trash?
- If we can finesse with number, why can't we also reverse finesse with number?
- A reverse with number is usually harder to read than a reverse with colour, but they can be a lot more efficient than colour + multiple correction clues (to prevent future bombs).
Travis Hall gives a basic explanation of number reverses:
Similarly, we often avoid number reverses, because if there’s both an available reverse to any card of that number and an immediately playable card of that number, the clue receiver has to guess at the correct move, and this can easily go wrong. Even so, when circumstance narrows the possibilities enough, we can sometimes do a number reverse safely.
Multicolour reverses with colour multicolour3,with a multicolourclue,
Travis Hall explains it well:
We usually avoid reverse finesses in multicolour, because although multi does connect with any colour, if we reverse multis then responses to our most common play clues - colour clues to a playable card - just stop, all of them, if a playable multi is in someone’s blind finesse position. That can be very difficult to work around.
- Multicolour reverses with a single colour can work, the most common situation being where the clue giver and receiver can both see a playable card of the colour clued either marked or in the finesse position in someone else's hand.
- Such a reverse may also trigger a hesitation play.
When to GD
- Plays extra cards for free from one or more hands.
- Protect cards
- Token is needed
GD without one of these benefits is usually of negative value:
- Limits the freedom to clue.
- Misleads the responder - the cards to the right of the copy is not trash.
Context
Using the last token 0clue tokens
Cause a valuable discard
- Marked in a hand
- Unmarked in a hand
Following player has a locked hand
- Cause a trash or duplicate discard e.g. black powder5 from 5 save.
- Cause a play
Negatives white5,with a 5clue,white4
Write notes if necessary.
- Keep track of your own negatives.
- Keep rack of all negatives.
Play finesse position e.g. multicolour bluff where:
- a colour-marked card has a negative colour
Multicolour bluff target is clued with a single colour
- if it can be clued red, but another colour is chosen = finesse
- if it can't be clued red = prompt
Cluing
Marking fewer than possible cards e.g. marking a single 2 with colour instead of multiple 2s with number = duplicate 2 in your hand
no prompt
no save = non-unique
- red yellow5 green5 blue5 white 2clue tokens
- card backcard backcard backcard back Alice 🡲 white1red2black powderwhite3 Bob 🡲
- Alice to Bob: these 2 cards are white.
- Bob plays white1.
- Cathy to Alice: these 2 cards are white.
- card back2,with a clue,card backcard backcard back4,with a clue, Alice 🡲 black powderred2black powderwhite3,with a whiteclue, Bob 🡲
- Alice plays white2.
- Bob discards his chop.
- Cathy discards.
- card backcard backcard backcard back4,with a clue, Alice 🡲 white4black powderred2white3,with a whiteclue, Bob 🡲
What is the best move for Alice?
A) clue white3,with a 3clue, B) clue white4,with a 4clue, C) play card back4,with a clue, D) discard card back4,with a clue, E) discard chop card back
- Alice's chop card was not marked before her free move to clue Bob, so she knows her oldest white card cannot be unique (white5).
- According to good touch, Alice can assume her white card is also not a 3 and could be a 4.
- Alice sees Bob has a valuable red2 on chop, marked white3 and unmarked white4 in his finesse position.
Trash bluffs
Stop trash bluffing 1s when 1k is not visible Would you trash bluff 5k when all 5s are not visible?
black powder1 tracking
when you can know 1k certain
how you can play chop 1s when 1k is still in the deck
tricks to save on saving black powder1
- when 1k is known somewhere and other cards are all marked later
- when 1k is known somewhere and there are promised cards in the same hand
- apply this principal generally is tricky because it can become unclear what has triggered a blind-play
slot 3 blind plays
certain 1k
uncertain 2
Consider this situation:
- Alice clues Donald's blue5,with a blueclue,
card backcard backcard backcard back Bob 🡲 blue1black powderblack powderblack powder Cathy 🡲 black powderblack powderblue5,with a blueclue,red5 Donald 🡲
- Bob sees blue1 and correctly assumes he has blue2blue3blue4 and mentally congratulates Alice on a great clue.
- So Bob saves red5:
card backcard backcard backcard back Bob 🡲 blue1black powderblack powderblack powder Cathy 🡲 black powderblack powderblue5,with a blue5clue,red5,with a 5clue, Donald 🡲
- Cathy discards.
- Donald discards.
- Alice discards.
- What should Bob do?
A) discard chopB) clue blue1C) play slot 1D) discard slot 1E) type "??" in chat
Always remember to:
- assume your teammates are giving valid clues (whether it's a good clue is a whole other question!)
- stop and consider all possibilities
- not type any reaction to a move in chat because it will usually spoil the game for everyone because you:
- tell everyone you found the move strange
- distract everyone from thinking about the best moves
- may provoke a player who is insecure or prideful into an argument
Passing back a finesse
- Normally we know that if we finesse a card and more than one player has a copy of the same finessed card, the first player will not play it because they see it in another hand, and the last player who does not see a future response must play the card.
- However sometimes we have a situation where it would be clearly a blunder to play.
- In the last example, Cathy's choice to discard instead of play for blue1 was the correct choice given she saw all the connecting cards in Bob's hand. Note that if Cathy had a critical card on chop, this finesse would be a blunder.
What if there were only one connecting card behind blue1?
- Alice clues Donald's blue4,with a 4clue,
blue1blue3black powderblack powder Bob 🡲 blue1black powderblack powderblack powder Cathy 🡲 black powderblack powderwhite4,with a white4clue,red5,with a red5clue, Donald 🡲
- Bob sees blue1 in Cathy's hand, so he saves red5
Or Cathy has both connecting cards as well?
- Double pass back
The point is that so long as an important card is not in danger of being discarded, the situation should always resolve itself without any more clues given.