## Rules of Kinderschnapsen

## The Rules of Kinderschnapsen (as used in ICAI-15 submission)

Kinderschnapsen is a 2-player card game of imperfect information but perfect recall.

### The Deck of Cards

From a standard Bridge deck 12 cards are used, queen (Q), jack (J), seven (7) and two (2) of 3 suits, spades (♠), hearts (♥) and diamonds (♦). We will denote cards by their value and suit throughout, e.g.: ♦Q, for the queen of diamonds. When referring to cards with the same value, but arbitrary suit we will write • for the suit. E.g. •J, for an arbitrary jack, etc.

### Card Values

Each card has an associated numerical card value. This value is taken to determine the points a player scores by a trick and furthermore determines the card hierarchy. The numerical card values are given in the following list:

•Q | •J | •7 | •2 |
---|---|---|---|

12 | 11 | 7 | 2 |

### Card strength

Card strength is a partial order depending on the trup suit. That means, that not any pair of cards has a stronger card. A card C1 is stronger than another card C2 if either

- C1 and C2 are of the same suit and C1 has a higher numerical value than C2.
- C1 is of trump suit.

### A Trick

The leading player chooses an arbitrary card from his hand and places it face up on the table. If the stock is open, the replying player may choose an arbitrary card, if the stock is closed he has to choose a cards following two rules:

- Follow suit of the leading card.
- Choose a card stronger than the leading card.

If in conflict, rule 1 is stronger. The replying player places the card face up on the table to complete the trick. The replying player does the trick, if his card is stronger, otherwise the leading player does the trick.

The player who did the trick takes the trick points, the sum of the cards values, and places the cards face down on a pile on his side of the table. The players are allowed to look at the cards in their pile at any time. They are not allowed to look at the opponents pile.

If the stock is open, each player takes the topmost card from the stock, starting with the winner of the trick. The player who did the trick leads the next trick.

### Closing the Stock

If the stock is open, the leading player may close the stock prior to playing the leading card. He does so, by placing the turnup card on top of the stock.

The stock is closed automatically if it runs out of cards.

### A Game

##### Dealing

A hand starts with the dealer shuffling the deck and dealing 3 cards to each player and 1 card face up on the table. The remaining deck is placed face down on the table and is referred to as the stock. The card lying face up on the table is called turnup, and determines the trump suit. It is considered the bottommost card of the stock.

##### Playing And Checking Out

The player opposite to the dealer starts leading the first trick. Tricks are played, until a player checks out of the hand or both players run out of cards. A player may check out of the hand immediately after scoring points by making a trick. The player making the very last trick, with both players holding no more cards, is given the chance to check out before the game ends with no check out.

##### Game Score

A player needs to score 46 trick points to win a hand. If a hand is ended, the winner of the hand is rewarded a game score of 1, 2 or 3, depending on whether the opponent scored more than 21 trick points, more than 0 trick points or did not score at all.

If no player checked out and the hand was ended automatically by the last trick, the winner of the last trick is rewarded a game score of 1.

### A Game

A game is a succession of hands. At the start of a game, each player holds a game score of 5 points. If a player wins a hand by a score of 1, 2 or 3, this score is subtracted from his game score, without writing negative numbers (that is, if a player holds a game score of 2 and wins a hand with a score of 3, his game score is set to 0). The function of being dealer of the hand alternates between the players. The player first reaching a game score of 0 wins the game.

### A Match

A match is played best of 1 or more games. E.g. the players arrange to play best of 5 (first to 3) games. The player dealing the first game is determined by any acceptable means. After that, the dealer of the first game of each game alternates. If Player 1 was dealing the first hand of the first game, Players 2 deals the first hand of the second game, etc.