OVERVIEW
Koi-Koi is a press-your-luck, set collection game played with beautiful Japanese "flower cards." There are 48 cards divided into 12 suits, a suit for each month of the year. Each month is symbolized by a flower or other plant and consists of 4 cards. As you complete card combinations, you decide whether to score points or keep playing. If you keep playing, you earn multipliers, but only one player will score points for the round, and as one player gains points, the other player loses them.
SETUP and BEGINNING OF THE ROUND
Everyone starts with 50 points. Each player has a hand of 8 cards, and 8 cards are dealt face-up to the table.
~ At the start of each round, check for instant win conditions: A set of 4 cards from the same month -OR- 4 pairs of matching cards. If so dealt, the instant winner gains 6 points, the opponent loses 6 points, and a new round is started.
~ If the round starts with either condition on the table, the round is redealt.
By default, each round starts with a "Bright Base Multiplier" equal to the number of Bright Cards face-up on the table. The winner's points earned that round is multiplied by the this number.
~ Example: If there are 3 Brights on the table, the multiplier is x3.
GAME PLAY
On your turn, choose 1 card from your hand to play to the table. You are trying to capture cards on the table with a card from your hand to complete card combos (YAKU) that are worth points. You capture a card on the table when it's the same month as the one you play.
~ If your card matches one on the table, place the card from your hand AND the captured card into your winning zone.
~ If it doesn't match, your card is simply added face-up to the table.
~ You must always capture if possible.
~ If there are 3 cards from the same month on the table, the matching card takes the entire set of cards.
Next, draw a card from the deck. If it matches a card on the table, add the both cards to your winning zone. Otherwise, add the card from the deck face-up to the table.
After you have played 1 card from your hand and one from the deck, the next player takes their turn.
KOI-KOI
After playing 1 card from your hand and 1 from the deck, check to see if you formed a yaku (card combo). If so, you must either score it and end the round, or choose koi-koi to continue playing.
~ SCORE: Gain points equal to the value of the yaku, plus any multipliers. Your opponent loses the points you gained, and the round ends.
~ KOI-KOI: The round continues. By default on BGA, your score multiplier increases by 1 each time you koi koi. You can koi-koi each time you complete a yaku, pushing your luck as many times as you like during a round, to increase the multiplier, but you will not score anything at all unless you form another yaku before the other player does.
ROUND END
A round ends in one of two ways:
~ WINNER: One of the players completes a yaku and chooses to end the round. The score points for their yaku and the other player loses points equal to that amount.
~ DRAW: All cards have been played from hand and no one has scored a yaku. By default on BGA, the start player scores 6 points and the other player loses 6 points.
By default, the round winner becomes start player for the following round.
GAME END
By default, the game ends after 6 rounds (half a year), but other game length options are available when you create a table.
At the end of the game, the player with the most points wins!
If at any point a player's points are reduced to zero, they immediately lose the game.
YAKU (card combinations)
There are 4 types of cards in the game: Brights, Animals, Ribbons and Chaff. There are yaku for each type and their point value varies. You can use the in game help icon to display a pop-up listing all the possible yaku and how many points they are worth.
All the yaku are combinative, except the "Bright" cards yaku, which are exclusive (you will always score the biggest available).
VARIATIONS
There are many options available when creating the table.
Soft Koi
The default selection. When a player calls Koi, the caller's multiplier increases by 1. You run the risk of your opponent making a yaku and scoring for the round before you can score yourself, but a lot of points are available if you push your luck.
Hard Koi
When you call koi-koi, the opponent's multiplier doubles (only once). If you manages to get at least 7 points, your score is doubled. There is less incentive to call koi-koi since you won't get a multiplier just for continuing the round. Instead, if you koi-koi and your opponent manages to score, their score will be doubled. If they also 7 or more points, then their score will be x4.
Draw Round Points
If players empty their hands and no one has completed a yaku by the end of the round, the hand can end without scoring or so either the dealer or non-dealer scores 6 points (and the other player loses 6 points).
Viewing Yaku
The Viewing Yaku are card combinations consisting of either the Cup and Moon or Cup and Curtain.
~ ENABLED (DEFAULT): Both yaku can be scored.
~ DISABLED: Neither yaku can be scored.
~ RAIN RUINS THE PARTY: Both yaku can be scored UNLESS a player captures a November (rain) card. In that case, the party is ruined and that player cannot score either yaku for that round.
Start Player
~ Winner starts the next month: The winner of the current month is start player for the next month (this is the default).
~ Loser starts the next month: The player who lost this month gets to play first next month.
~ Alternating starting player: The player who didn't get to play first this month will play first the following month.
