Chess variations

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:

Just as in traditional chess, chess variants can be played over-the-board (OTB), or by correspondence.

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 extraordinarily huge. 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.

Today's chess exists because of variations someone made to the rules of an earlier version of the game. Movement of the queen was once limited to only a single square in a diagonal direction (a ferz). Today the queen still starts next to the king, but has gained new movement, and is now part of today's rules of chess. Chess enthusiasts still often like to try variations of the rules and in the way pieces move. Chess games which are different from today's standard rules are called chess variants.

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.

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