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User:Sammy McSam/Hanabi page 2
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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
Black powder 1
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
- Hand management is important in high level play to keep as many non-trash cards in the game for as long as possible.
When to skip players
(and how to irritate them )
- Opening with no information on any of your cards.
- The player(s) skipped have duplicate cards that need to be marked with a good touch play clue.
- If you have been the target of a trash bluff and not yet discarded cards to the right of the trash cards.
- Players in front of you have trash.
- The player behind you has many plays.
Double Discard Avoidance (DDA)
- Many players have incomplete or non-existent methods for managing DDA because it is difficult as it requires a lot of contextual awareness.
- Players need to be aware of how many opportunities there are to mark double chop cards.
- Anytime a chop card is marked with a number of the same rank visible in the next player's hand DDA should be considered.
- Or even if the double chop players are not next to each other but the in-between players are busy.
8 clue tokens
Efficiency
Bluffs
- Bluffs are powerful...
- Easiest way to mark nice cards
Maximising 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
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 1 clue tokens or 7 clue 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 🡲
- With black powder: 1 bluffs are black powder1 promise bluffs unless black powder1 is known to Alice and the receiver.
Would you trash bluff 5k when all 5s are not visible?
white3,with a 3clue,
Reverses with number
- 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.
multicolour3,with a multicolour clue,
Multicolour reverses with colour
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 receiver - the cards to the right of the copy is not trash.
Context
Using the last token 0 clue 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
Write notes if necessary.
- Keep track of your own negatives.
- Keep track 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
- redyellow5green5blue5white 2 clue 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 white clue, Bob 🡲
- Alice plays white2.
- Bob discards his chop.
- Cathy discards.
- card backcard backcard backcard back4,with a clue, Alice 🡲 white4black powderred2white3,with a white clue, Bob 🡲
- 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.
black powder1
Black powder 1 tracking
black powderblack powderblack powderred1,with a 1clue, Bob 🡲 black powder1black powderblack powderblack powder Cathy 🡲
- First clue of the game. Alice to Bob: this card is a 1.
- Bob plays red1,with a 1clue,.
- Cathy knows that Bob would not be able to play if he cannot see black powder1.
- Cathy cannot see black powder1 so she must have black powder1 in her hand.
Cathy knows that ordinarily her black powder1 will be saved once it reaches her chop. But what if black powder1 is in her slot 1?
If Cathy tracks her leftmost unmarked card, once black powder1 reaches her chop, she already knows it and black powder1 does not need to be saved at all!- Alice to Bob: these two cards are 1s.
redyellow1green2blue1whiteblack powder3 black powderwhite1,with a 1clue,red1,with a 1clue,black powder Bob 🡲 black powder1black powderblack powderblack powder Cathy 🡲
- Bob plays red1,with a 1clue,.
- Cathy knows that ordinarily Bob will play the leftmost 1 first since play clues are left-focused. But since Bob played his rightmost 1, logically this communicates something extra: that Bob can see black powder1. So Cathy knows she has black powder1 in her hand and notes that her leftmost can be black powder1.
When all players understand that a rightmost 1 play means they see black powder1, Alice can even mark trash cards:
redyellow1green1blue1white1black powder2 blue1,with a 1clue,green1,with a 1clue,red1,with a 1clue,black powder Bob 🡲
black powder1black powderblack powderblack powder Cathy 🡲redyellowgreenbluewhiteblack powder
black powderblack powderblack powderred1,with a 1clue, Bob 🡲 black powderblack powderblack powderblack powder Cathy 🡲 yellow1yellow3yellow5black powder1 Donald 🡲
- Alice to Bob: this card is a 1.
- Bob plays red1,with a 1clue,.
- Cathy clues yellow to Donald.
- Donald knows that Bob would not be able to play if he cannot see black powder1.
- After Cathy clues yellow, the leftmost possible position for his black powder1 has moved to his chop.
Taking example 2 further, we can even play all slot 4 1s when black powder1 is still in the deck!
- Alice clues 1s to Cathy.
- Bob clues 1s to Donald.
redyellowgreenbluewhiteblack powder black powderblack powderred1,with a 1clue,green1,with a 1clue, Cathy 🡲 black powderblack powderyellow1,with a 1clue,blue1,with a 1clue, Donald 🡲
- Cathy does not see black powder1 so she plays her leftmost red1,with a 1clue,.
- Donald also does not see black powder1 so he plays his leftmost yellow1,with a 1clue,.
red1yellow1greenbluewhiteblack powder black powderblack powderblack powdergreen1,with a 1clue, Cathy 🡲 black powderblack powderblack powderblue1,with a 1clue, Donald 🡲
Since both players have communicated that they do not see black powder1, it is still in the deck and next turn everyone can play their remaining 1s.
Applying this principal generally is tricky because it can become unclear what has triggered a blind-play
slot 3 blind plays
- When you track black powder1, the position becomes known when the leftmost possible position reaches your slot 3 and your slot 4 is not saved.
card backcard backblack powder1card back You 🡲
red2
uncertain 2s
Since 2s (& black powder4) are so valuable, if a player is allowed or encouraged to discard a 2 when it could have been prevented or even just delayed, it is logical that there is another copy of that card in the same hand or visible in someone else's.
- So you can track it like black powder1 and also blind play it before it is marked as soon as it is playable.
- Alice clues Donald's blue5,with a blue clue,
card backcard backcard backcard back Bob 🡲 blue1black powderblack powderblack powder Cathy 🡲 black powderblack powderblue5,with a blue clue,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 blue 5clue,red5,with a 5clue, Donald 🡲
- Cathy discards.
- Donald discards.
- Alice discards.
- What should Bob do?
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 white 4clue,red5,with a red 5clue, 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.
Endgame
When to discard, play, empty clue, clue duplicates and advanced techniques.
Trash moves
When a direct clue is blocked by trash cards, we can finesse the playable card with a single clue that marks one or more trash cards.
1. Trash push
- Trash push is optimal because
- Where the trash cards include the chop card, the clued card is the rightmost unmarked card (i.e. touching the chop trash card).
red5yellow5green5blue5white3multicolor5 multicolour4white4multicolour1,with a 1clue,red1,with a 1clue, Bob 🡲
2. Trash pull
- Pull is always inferior to push, both in order of interpretation and in quality.
- Where the trash cards do not include the chop card, the clued card is the leftmost unmarked card (i.e. finesse position).
red5yellow5green5blue5white3multicolor5 multicolour4,with a multicolour clue,white4multicolour1,with a multicolour clue,red1 Bob 🡲
- Alice to Bob: these two previously unmarked cards are blue.
The critical move
To work out the most efficient sequence of moves, you need to determine three things:
- Critical colour
- the colour that takes the most turns to complete.
- (i.e. must start as soon as possible to maximise the score).
- Critical card
- the first card of the critical colour.
- Note: this can be a duplicate of a card already marked!
- Critical move
- the move that makes the critical card play.
- Note: this can be a clue, play or discard.
- red2yellow5green5blue5white2
card backcard backcard backcard back3,with a 3clue, Alice 🡲 white3black powderblack powderred4,with a red 4clue, Bob 🡲 black powderblack powderblack powderred5,with a red 5clue, Cathy 🡲 black powderblack powderwhite4,with a white 4clue,white5,with a white 5clue, Donald 🡲
- red3red4red5black powder
- white,with a white clue,white3black powderwhite4 black powderblack powderblack powderwhite5
- Play red3 red3red4red5white,with a white clue, black powderwhite3black powderwhite4 black powderblack powderblack powderwhite5
- Clue white3 white,with a white clue,white3black powderwhite4 red3red4red5white5
- red2yellow5green5blue5white2 A) Play red3 B) Clue white3
card backcard backcard back4,with a 4clue,card back3,with a 3clue, Alice 🡲
white3black powderblack powderblack powder Bob 🡲
black powderblack powderblack powderred5,with a red 5clue, Cathy 🡲
black powderblack powderblack powderwhite5,with a white 5clue, Donald 🡲
- red3black powderblack powderred4 black powderblack powderred5black powder
- white,with a white clue,white3black powderblack powder black powderwhite4black powderwhite5
2. Serialise:
- red3black powderblack powderred4 white,with a white clue,white3red5black powder black powderwhite4black powderwhite5
- white,with a white clue,white3black powderblack powder red3white4black powderred4 black powderblack powderred5white5
- Identify the critical colour - usually the player with the most unique cards, or consecutive cards of the same colour.
- Work out how many clue tokens are needed to reach the critical player.
- If you only have one unique card, discarding although counter-intuitive, is often the best move to generate a token!
This was a simple example. Test yourself with some more complex examples!
When to discard?
The endgame should be the easiest part since we can just calculate all possibilities, yet it is really hard to master.
With 5 flamboyants, generating a token from a discard instead of a play may be the only way to reach the start of the critical path.
- 2cards in the deckred4yellow5green5blue5white3 0 clue tokens
card backcard backcard backcard back5,with a 5clue, Alice 🡲 black powderblack powderblack powderblack powder Bob 🡲 black powderblack powderwhite4,with a white 4clue,white5,with a white 5clue, Cathy 🡲
- black powderblack powderwhite4 black powderblack powderwhite5
- To reach Cathy with a least 1cards in the deck remaining, only one of Bob or Alice can draw a card.
- Alice cannot clue (0 clue tokens) and must generate a token for Bob so that he can give a stall clue to avoid drawing the last card.
- Without 5 flamboyants Alice would just play her 5 which generates 1 clue tokens.
- With 5 flamboyants Alice can't know if playing her 5 will generate a token, so Alice discards and plays after Cathy's critical card (white4).
General case with 5 flamboyants
When Alice does not have a card of the critical colour, then discarding is better than playing!
Getting bottom decked
...is arguably the most 'unfair' part of Hanabi .
Here's a candidate for the worst ever bottom-decked situation: all three blue1 in the last 5cards in the deck cards
Order of plays
Where the order may seem arbitrary, prioritise from most out-of-order to consecutive plays e.g.:
- white5 white4 white3
- white4 white3 white5
- white3 white4 white5
Replace flamboyant
The decision of which card to replace (or to skip) can communicate information to the team. Priority highest to lowest:
- lowest rank unique
- lowest rank non-unique
- duplicate of an unmarked card
- duplicate of a marked card
- trash of number corresponding to the slot position of a playable card
- black powder5
- skip
When there is no gain in returning a card playable in the future - either the immediate flamboyant will play from discard pile or , the decision of which trash card to replace into the deck can be a clue in itself corresponding to the slot position of a player. When playing with black powder and 4 or 5 players, replacing an available 5k trash card indicates no playable card is visible.
5 Flamboyants
Don't let the 5 fool you - there are actually six randomly selected actions:
- Gain 1 clue tokens
- Gain 1 clue tokens & remove a mistake
- card3,with a 3clue, Give number clue
- card,with a Hanabi card clue, Give a color clue
- Replace a card from the discard pile into the deck
- Play a card from the discard pile
A 7th stack bonus is always irrelevant (and on BGA always gain 1 clue tokens clue token), since there is no 8th stack.
Available Tokens
idealgame without flamboyants:
3players5cards in handred5yellow5green5blue5white5
50 (deck) ➖ 25 (played) ➖ 12 (3players× at least4cards in hand) 🟰 13 discards
13 clue tokens (discards) ➕ 8 clue tokens (start) ➕ 5 clue tokens (red5 yellow5 green5 blue5 white5) ➖ 1 clue tokens (last 5) 🟰 25 clue tokens
25 clue tokens ➗ 25 🟰 1 clue tokens / card
5players4cards in handred5yellow5green5blue5white5 ⇨ 22 clue tokens ➗ 25 🟰 .88 clue tokens / card
2players6cards in handred5yellow5green5blue5white5multicolor5black powder1 ⇨ 39 clue tokens ➗ 35 🟰 1.1 clue tokens / card
