The rules of this game are mostly identical to Oicho-Kabu, with some notable differences:
Game setup is the same as in Oicho-Kabu; it involves choosing a dealer - 親 [おや, oya], deciding the seating arrangement of the other players, and shuffling the deck. Certain ground rules should also be agreed upon before play begins.
A kabufuda deck is used. This simple deck contains 40 cards, consisting of four identical series of the numbers 1 to 10.
Since kabufuda decks are somewhat uncommon, they are often emulated with a hanafuda deck by removing all November and December cards and assigning values to the remaining cards based on month order. So all January cards are 1, February cards are 2, and so on, up to October which is 10.
Alternatively, one can take an international 52-card deck and remove all Kings, Queens, and Jacks, leaving only the pip cards. Ignoring suits (and counting the Aces as 1), the result is exactly equivalent to a kabufuda deck.
In addition to the deck, a collection of chips to represent points will be highly useful. Using different colours of chips for each player will help with tracking bets.
Before play begins, the group should agree on the following:
To begin, each player draws a card from the deck. The player with the lowest number becomes the dealer, and the remaining players seat themselves in order anti-clockwise around the table- the second-lowest number sits to the right of the dealer, third-lowest to the right of them, and so on. Since play begins with the dealer and progresses anti-clockwise, there is a distinct advantage to sitting close to the dealer’s right.
If the dealer represents an establishment- say, when playing at a casino or gambling parlour- then their role will obviously be fixed, though the other players may still use this process to determine their seating order.
In the event of a tie, the players in question should draw a second card and compare again.
When playing with a hanafuda deck, the ranks of the cards can be used to break ties in the usual manner- Brights beat Animals, which beat Ribbons, which beat Chaff.
With a standard 52-card deck, suits could be used to break ties instead.
Over the course of the round, each player attempts to form a hand whose total value is as close as possible to 9. Totals that go over 9 ‘wrap around’ by discarding the tens digit. So 10 is equivalent to 0, 11 is equivalent to 1, and so on, much like Baccarat. Similar to other banking games, the players are not competing against each other, but are only aiming to beat the dealer.
Only the dealer has a ‘hand’ in the traditional sense- the players hold no cards of their own. Instead, four hands are dealt to the table in a step-by-step process, and the players bet on the hands they consider most likely to win against the dealer’s.
The dealer shuffles the deck and places 4 cards are dealt face-down to the table in a row. This is known as the first field- each of these four cards will form the basis of a hand.
Next, the dealer draws a card from the deck and places it face-down in front of them, without looking at it. This card will be the first in the dealer’s hand.
Then, starting from the right of the dealer and working anti-clockwise, the players take turns to bet on these potential hands.
Each player may bet on only one card on the first field, and multiple players cannot bet on the same card.
They signal their bets by placing the appropriate number of chips on top of each card, based on the agreed-upon fixed betting amount.
The dealer now deals 4 cards face-up to the table, one below each of the cards in the first field. This row is the second field, and each card forms a hand with the one above it; that is to say, each column of cards on the table is a hand.
Afterward, the dealer adds a second face-up card from the draw pile to their hand.
Finally, the first field and the dealer’s first card are revealed. These cards are turned face-up for all to see.
The dealer’s hand is then compared with each of the four hands on the table.
This comparison is performed independently for each of the four hands- it is entirely possible for the dealer to win against some hands while losing against others.
There are two special Yaku that can affect the showdown:
“Dealer 4 and 1” is also order-sensitive- the first card must be a 4, and the second card must be a 1. They do not apply if the order is reversed!
No particular setup is given for playing additional rounds. When playing at a casino or parlour, the dealer will remain the dealer, though the players may cycle their seating positions.
In casual games, the dealer may either remain fixed, or lose their role whenever their hand loses against every hand on the table. In this case, the player to their right becomes the next dealer.