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Flexible Chess (F-chess)

This page contains one or more presets for playing a game online with Game Courier, an online server for playing Chess variants by correspondence.

In Flexible Chess (F-chess) the rules are the same as in orthodox chess except that knights and bishops are initially placed outside the board. Any empty square on the first rank can serve as initial square, creating great opening flexibility without departing from standard opening strategy. Bishops and knights can be introduced via any empty square on the first rank and move immediately, effectively a double-move. Pieces can be introduced at any time, provided that a move exists that originates from the first rank. For instance, if the white queen has already moved away, a knight can be introduced via d1, thus reaching the square b2 (provided that it is empty). The bishops must be inserted on different colour squares. Flexible Chess is intended as an alternative to standard chess, radically increasing the ramification of openings. By waiting a few moves before introducing an external piece, a player can hide his strategical intentions. A Zillions implementation and more information is here.

  In this example, the white-squared bishop can move from b1 or f1.
  Captures are also possible.


The following preset makes a good validity check of moves. Moves are automated. You can move pieces by clicking on them. At promotion you will be asked what piece you prefer.

Flexible Chess

Flexible Chess (only the bishops are external)

Flexible Chess (only the knights are external)



This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.


By M Winther.

Last revised by M Winther.


Web page created: 2012-01-25. Web page last updated: 2012-01-25