Chess variant

A chess variant (or unorthodox chess) is a game "related to, derived from, or inspired by chess". The difference from chess might include one or more of the following:

Regional chess games, some of which are older than Western chess, such as chaturanga, shatranj, shogi, and xiangqi, are typically called chess variants in the Western world even though they are not derived from, or inspired by, western chess. They have some similarities to chess and share a common game ancestor.

The number of possible chess variants is virtually unlimited. Confining the number to published variants, D. B. Pritchard, author of The Encyclopedia of Chess Variants, estimates that there are well over 2,000.

In the context of chess problems, chess variants are called fairy chess, fantasy chess, or heterodox chess. Some chess variants are used only in problem composition and not in actual play.

These chess variants are derived from chess by changing the board, board setup, pieces, or rules.

Many variants employ standard chess rules and mechanics, but vary the starting position of the pieces or number of pieces.

These variants use standard boards and pieces, but the pieces start on nontraditional squares. In most such variants, the pawns are placed on their usual squares, but the position of other pieces is either randomly determined or selected by the players. The motivation for these variants is usually to nullify established opening knowledge. The downside of these variants is that the initial position usually has less harmony and balance than the standard chess position.

These variants use standard chess pieces on a standard board, but players begin with unorthodox numbers of pieces. For example, starting with multiple queens or fewer pawns. Many such games use unbalanced starting positions, with one player having more or less of a particular piece than the other player.

In these variants, the same pieces and rules as in chess are used, but the board is different; It can be smaller or larger, the shape of either the board or individual spaces can be non-square or modular, or it can even be extra-dimensional. The movement of pieces in some variants is modified in concurrence with the geometry of the gameboard.

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