Fish is a memory and strategy card game. It is also known as Canadian Fish, Literature, and Extreme Go-Fish.
First, the four 8s in the deck are removed, leaving 48 cards. This game can be played with either 6 or 8 players, on teams of 3 or 4, respectively. The 48 cards are made into 8 "half-suits". They are first divided into suit (spades, hearts, diamonds, clubs) and then into "high" (9-A) and "low" (2-7).
Similarly to regular Go-Fish, the objective of the game is to obtain all the cards of as many half-suits as possible.
On each turn, one player A of one team asks a player B of another team a question such as, "Do you have the 2 of spades?" In order to ask an B if she has a certain card, player A must have another card in that same half-suit different from the card for which she is asking. In this scenario, player A has either the 3, 4, 5, 6 or 7 of spades, but not the 2. If player guesses correctly, she receives the card and continues her turn (player A may proceed to ask player B for another card or ask a different player on the opposing team for a card). If not, the turn goes to player B.
The game is won (or lost) by "claiming" a half-suit. This occurs when a player believes that his team holds all the cards of some half-suit. Moreover, the player must know where each of the cards of the half-suit lie. A typical claim would be along the lines of, "I have the 2 and 3 of spaces, teammate A has the 4 and 5, and teammate B has the 6 and 7". An incorrect claim occurs when the player incorrectly guesses where one or more of the cards of the half-suit lie. If the claim is correct, the team with the player making the claim wins that half-suit, and the other team wins the half-suit otherwise. A claim may be made at any time, and a correct claim does not affect turn order. However, an incorrect claim, in the event that it is made by a team during its turn, results in the turn being awarded back to the player on the opposing team who most recently had a turn. At the end of the game, the number of half-suits won determines the winner.
The most basic (and most important) aspect of gameplay is memory: one must keep track of the locations of cards in relevant half-suits and in general remember as much of the information that has been revealed as possible. That being said, there are many different strategies that can be used in Fish, but like in Bridge, all signals must be made clear to opponents; that is, all information must be public. Some possible strategies are:
- continuing to "fish" for the same suit before asking for another one, as to avoid revealing more information than necessary, in particular making one vulnerable in multiple suits.
- ensuring, one by one, that each player on the opposing team no longer holds cards in a given half-suit before asking others on the opposing team for cards in the half-suit.
- locking out members of the opposing team, most commonly, when two players on opposite teams are known to hold all cards of one suit; neither player should not be asked for anything unless there is 100% certainty that she is holding the desired card.
- responding to unsuccessful attempts by opponents to "fish" cards of a suit by fishing cards of the same suit from the opponent (if possible); probabilistically, one has always the advantage in such exchanges whenever it is his or her turn.
- "signaling" to teammates the cards one holds in a half-suit known to be controlled by the team. A popular but inefficient convention is for one player, in order from top down, to ask (knowing the answer will be 'no') for all of the cards she is not holding.