Koi-Koi

Also known as Koi Koi, Hanafuda Koi-Koi

Players

2 players

Deck

1 hanafuda pack (48 flower cards, four to each of the twelve months)

Time

20-40 minutes

Difficulty

Medium

Category

Matching & collecting

Setup

Koi-Koi is played with hanafuda, and there is no substituting a Western pack: the cards have no ranks and no numbers on them, only pictures, and the whole game turns on which of four picture types a card is. Buy the pack or you cannot play. Hanafuda cards are small, thick and stiff, and they are meant to be snapped down flat rather than fanned.

The pack holds forty-eight cards in twelve months, four to a month, and the month is the only thing that makes two cards match. January is pine, February plum, March cherry, April wisteria, May iris, June peony, July bush clover, August pampas grass, September chrysanthemum, October maple, November willow and December paulownia.

Cutting across the months are the four card types, and these are what score. Five cards are brights, the large ceremonial pictures: the crane, the cherry-blossom curtain, the full moon, the rain man under his umbrella in the willow month, and the phoenix. Nine are animals — the group's name rather than a description of it, since the iris month's plank bridge and the chrysanthemum's sake cup are counted among them and neither is an animal at all; the rest are the bush warbler, the cuckoo, the butterflies, the boar, the deer, the geese and the swallow. Ten are ribbons: three red ones carry writing on them, three are blue, and the remaining four are plain red. Everything left over, twenty-four cards, is plains — worth nothing individually and quite capable of winning you the round in bulk.

Pick a first dealer any way you like; the traditional method is that each player draws a card and the earlier month deals, a tie inside one month going to the higher-value card. The dealer gives eight cards to each player and lays eight face up in the middle to form the field, dealing in packets of four — or of two — rather than singly, and the remaining twenty-four go face down as the draw pile. The dealer then takes the first turn — which, since the winner of a round normally deals the next, is a small compounding advantage and the reason winning early rounds is worth more than the raw score suggests.

If all four cards of one month land in the field, nobody can ever match them, since no player and no draw can produce a fifth. The deal is scrapped: throw the cards in, shuffle and start again. A field holding four separate pairs is treated the same way. Some tables keep a four-of-a-month field instead and let the dealer sweep the four and replace them, or hand the dealer the round outright. Three of a month in the field is fine and is in fact a prize, because the player who produces the fourth takes all four.

One consequence of those numbers is worth noticing before you start: the draw pile is never used up. Eight cards each means eight turns each and sixteen draws in all, so eight cards are still face down when the round ends. A round is bounded by the hands, not by the pile.

Play

A turn comes in two halves, and both halves are the same simple matching.

First, lay one card from your hand face up. Playing a card is compulsory — if nothing in your hand matches anything in the field you must still put one out, and choosing which one to give away is a real decision. Whether holding a match obliges you to use it is not agreed: one account says outright that it does not, and that you may put down a dead card while keeping a matching one back, where the other's wording reads as though you must match when you can. Settle it before you start. What is not in doubt is that a card laid onto its own month takes the capture — you cannot play the match and then decline it. If the field holds a card of the same month, take both and add them to your captures. If the field holds nothing of that month, your card stays in the field and is now available to your opponent.

Second, turn the top card of the draw pile face up. It behaves identically: a month match takes both cards, no match leaves it lying in the field. The drawn card can match the card you have just played out, in which case you capture the pair you have only this second created.

Where three cards of one month are already sitting in the field, the fourth takes all four at once, whether you play it from hand or turn it off the draw pile — the biggest single match the rules allow.

A single turn therefore takes nothing, two cards or four in each half, and on a rare turn where both halves land on a three-card month it can take eight. Where a month offers two possible matches you choose which card to take, and choosing well is where most of the ordinary decisions in the game are — the field is public, so you can see what your opponent needs almost as clearly as they can. Captures are laid out face up in front of you and grouped by type, never hidden.

THE DECISION

After the draw, check what you have captured. If your captures now complete a scoring combination — a yaku — that you did not have when the turn began, or extend one you already had, play stops and you must choose one of two things.

• Stop, which is called shōbu. The round ends immediately. You score everything your captures are worth and your opponent scores nothing at all.
• Call koi-koi and carry on. Nothing is banked. Play resumes, and you may only stop later if you have improved on what you already had.

Koi-koi means roughly "come on, come on", and it is a bet made against yourself. It is the only real decision in the game and the reason the game has a name. Calling raises what you might take, but it also opens a door for your opponent: complete a yaku before you complete another and they will simply stop, taking the round while you take nothing, and your call will have made their score bigger.

When you stop, or when your opponent stops after your call, the round is over even if both players still hold cards.

RUNNING OUT

If both hands empty with nobody having stopped, the round is dead. Neither player scores for their captures, however good they look on the table — a player who called koi-koi and never improved on it loses the lot — and the same dealer gathers the cards and deals again. Whether the dealer is paid for the wasted round is not agreed: one account makes it the rule, calls it the dealer's privilege, oya-ken, and puts it at a point; the other files it as a house rule and gives the usual payment as either one point or six. Say which you are using before the first deal.

A full game is twelve rounds, one per month of the hanafuda year. Six and three are both common when time is short, and some play to a target instead — first to fifty points. It is worth agreeing the length before the first deal, since it changes how recklessly you should be calling koi-koi late on. The winner of a round deals the next one.

Goal & scoring

Each round goes entirely to the player who stops with a yaku; there is no splitting and no consolation. Add the rounds up and the higher total wins the game.

Everything you have captured counts at once, so a set of captures can satisfy several yaku together. The sake cup shows this off: it is an animal, it forms both viewing combinations, and it counts as a plain as well towards the ten-plain total — four yaku out of one card.

The brights never stack. You score the single best bright combination you hold and not the lesser ones underneath it, and the rain man of the willow month is the awkward card there, because it blocks the top-scoring versions while still rescuing a hand that would otherwise be one bright short.

How far that grading reaches is where the two accounts part company, and it moves scores a long way. On one, the ribbons and the animals work like the brights — best in each group only — so the red poetry ribbons and the blue ones make a single combination worth ten rather than two worth five apiece, neither pays again inside the five-ribbon total, and the named combination instead grows by a point for each extra card of its type. On the other, and in older descriptions generally, they stack: red and blue score separately and all six still count towards the five-ribbon total on top. The table below gives the stacking form. Agree which you are playing before the first round.

The three counting yaku — animals, ribbons and plains — pay at their threshold and then a further point for each card past it, so they keep growing for as long as the round runs. This is what makes koi-koi tempting: a player already holding five animals gains a point for every additional animal captured, without needing anything new to appear.

Once your total is settled, two multipliers apply. A total of seven or more is doubled, which is why the difference between six points and seven is worth more than one point; that one was a house rule first and was only later taken into the game proper, and a few tables still leave it out. The other belongs to the koi-koi call, and here both accounts agree: if your opponent called koi-koi at any point in the round and you are the one who stops, your score is doubled. The punishment for a greedy call is severe, and how many times they called makes no difference. Tables vary: some give the doubling to the caller rather than to their opponent, some to whoever stops if anybody called at all, and some scale it with the calls, the multiplier being one more than the number made. The two multipliers compound rather than replace each other, so a nine-point hand taken against a caller is worth thirty-six. Fix which you are using before the first round; on a big hand it decides the game.

The game is also played for a stake per point rather than a running total. One account describes the zero-sum form built for that, where whatever the winner scores comes off the loser.

Variants

Sake cup rulings — The chrysanthemum sake cup earns its reputation: as standard it is an animal, it counts as a plain as well for the ten-plain total, and it forms both viewing yaku with the moon and the cherry curtain, so one card feeds four combinations. The house rules recorded for it cut it back rather than extend it. One is to drop the two viewing yaku altogether, since a five-point pair of cards makes early rounds swing hard — many video-game versions offer that as a switch — or to allow them only to a player who already holds some other yaku. Others restrict the card itself: let it count as an animal or as a plain but not both, or as an animal only. There is also a weather ruling, under which willow cards in the field rain off the blossom viewing and paulownia cards fog out the moon viewing until they have been cleared away.

Lucky hands — The two lucky hands, or teyaku, are standard rather than optional, and there are only these two. Teshi is all four cards of one month in your hand; kuttsuki is four separate pairs. Either is declared at once and takes the round for a flat six points, with the claimant dealing next; if both players have one the round is a draw and the same dealer deals again. Accounts differ on a player holding both hands at once — six points on some, twelve on others — so settle that in advance. The reasoning behind paying for them at all is that these hands are miserable for capturing: the six points are there to make up for a bad deal rather than to reward a good one. Some tables take that further and treat both hands as a misdeal instead, exactly as they would if the combination had been dealt to the field.

Multiplier conventions — Some tables drop the doubling at seven points, so a big hand pays only what it is worth on the card — that multiplier began as a house rule anyway. The koi-koi doubling is redirected as readily as it is dropped: to the caller instead of their opponent, or to whoever stops if anybody called at all. It can also be made to scale with the calls, the multiplier running one higher than the number made, so a second call pays three times and a third four. A different lever again is the opening field: borrowing from Hachi-Hachi, some tables double the round's score when a bright turns up among the eight, and raise the multiplier once more for every further bright. These choices decide whether one bold round can win the game, so they are worth more thought than any single yaku value.

Round count and the dealer — Twelve rounds, one for each month, is the standard length; six and three are both common, and playing to a target of fifty points instead is a third option. Who deals after a drawn round varies: the same dealer deals again as standard, sometimes taking a point or six for the privilege, but the deal may instead pass to the other player, or the round may be awarded to whoever last formed or improved a yaku. Longer games favour steady small yaku; a three-round game rewards calling koi-koi much harder.

• classic
• luck
• memory
• strategy
• travel
• two-player

Rules checked against Wikipedia, Fuda Wiki, Board Game Arena game help, Sloperama hanafuda rules, Gambiter, Hanafuda Legends, GameDesign.jp.