A chess variant is a game "related to, derived from, or inspired by chess". Such variants can differ from chess in many different ways, ranging from minor modifications to the rules, to games which have only a slight resemblance.
"International" or "Western" chess itself is one of a family of games which have related origins and could be considered variants of each other. Chess is theorised to have been developed from chaturanga, from which other members of this family, such as shatranj, shogi, and xiangqi, also evolved.
Many chess variants are designed to be played with the equipment of regular chess. Although most variants have a similar public-domain status as their parent game, some have been made into commercial, proprietary games. Just as in traditional chess, chess variants can be played over-the-board, or by correspondence. Some internet chess servers facilitate the play of some variants in addition to orthodox chess.
There are thousands of known chess variants (see list of chess variants). The Classified Encyclopedia of Chess Variants catalogues around two thousand, with the preface noting that — with creating a chess variant being relatively trivial — many were considered insufficiently notable for inclusion.
The origins of the chess family of games can be traced to the game of chaturanga during the time of the Gupta Empire in India. Over time, as the game spread geographically, modified versions of the rules became popular in different regions. In Sassanid Persia, a slightly modified form became known as shatranj. Modifications made to this game in Europe resulted in the modern game. Courier chess was a popular variant in medieval Europe, which had a significant impact on the "main" variant's development.
Other games in the chess family, such as shogi (Japan), and xiangqi (China), are also developments from chaturanga made in other regions. These related games are considered chess variants, though the majority of variants are, expressly, modifications of chess. The basic rules of chess were not standardised until the 19th century, and the history of chess prior to this involves many variants, with the most popular modifications spreading and eventually forming the modern game.
While some regional variants have historical origins comparable to or even older than chess, the majority of variants are express attempts by individuals or small groups to create new games with chess as a starting point. In most cases the creators are attempting to create new games of interest to chess enthusiasts or a wider audience. Variants normally have the same public domain status as chess, though a few (such as Knightmare Chess) are proprietary, and the materials for play are released as commercial products.
The variations from chess may be done to address a perceived issue with the standard game. For example, Chess960, which randomises the starting positions, was invented by Bobby Fischer to combat what he perceived to be the detrimental dominance of opening preparation in chess. Several variants introduce complications to the standard game, providing an additional challenge for experienced players, for example in Kriegspiel, where players cannot see the pieces of their opponent. A handful, such as No Stress Chess, attempt to simplify the game, so as to be attractive to chess beginners.
The table below details some, but not all, of the ways in which variants can differ from the orthodox game:
|Difference from regular chess||Example variant|
|Different starting position||Chess960 - starting position randomly selected from 960 possible options|
|Non-standard pieces||Almost Chess - uses chancellors (which can move as a rook or a knight) instead of queens|
|Different victory conditions||Losing chess - objective is to lose all one's pieces|
|Players have incomplete information regarding the game state||Kriegspiel - players cannot see the pieces of their opponent, and have to deduce or guess where they are likely to be|
|Elements of chance||Dice chess - dice rolls determine which pieces can move on a turn|
|Non-identical setup for white and black||Dunsany's Chess - pits a regular chess army versus a large army consisting only of pawns|
|Different sized or shaped board||Infinite chess - the board is unbounded|
|Multiple boards||Alice Chess - pieces switch between the two boards when they move|
|Three or more dimensions in which pieces can move||see three-dimensional chess|
|Board other than lattice of squares||Triangular Chess - playing board is 96 triangular cells|
|More than two players||Quatrochess - played with four players|
Fairy chess gave rise to the term "fairy chess piece" which is used more broadly across writings about chess variants to describe chess pieces with movement rules other than those of the standard chess pieces. Forms of standardised notation have been devised to systematically describe the movement of these. A distinguishing feature of several chess variants is the presence of one or more fairy pieces. Physical models of common fairy pieces are sold by major chess set suppliers.
While chess, shogi, and xiangqi have professional circuits as well as many organised tournaments for amateurs, play of the majority of chess variants is predominately on a casual basis.
Some variants have had significant tournaments. Several Gliński's hexagonal chess tournaments were played at the height of the variants' popularity in the 1970s and 1980s. Chess960 has also been the subject of tournaments, including in 2018 an "unofficial world championship" between reigning World Chess Champion Magnus Carlsen and fellow high-ranking Grandmaster Hikaru Nakamura.
Several internet chess servers facilitate live play of popular variants, including Chess.com, Lichess, and the Free Internet Chess Server. The software packages Zillions of Games and Fairy-Max have been programmed to support many chess variants.
Play in most chess variants is sufficiently similar to chess that games can be recorded with algebraic notation, although additions to this are often required. For example, the third dimension in Millennium 3D Chess means that move notation needs to include the level number, as well as the rank and file — N2g3, means a knight move to the g3 square on the second level. When fairy chess pieces are used, notation requires assigning letters for those pieces.
Various publications have been written regarding chess variants. Variant Chess magazine was published from 1990–2010, being an official publication of the British Chess Variants Society from 1997. This outlined and introduced multiple variants, as well as containing in-depth analyses.
A leading figure in the field was David Pritchard, who authored several books on the topic. Most significantly, he compiled an encyclopedia of variants which outlined thousands of different games. Following Pritchard's death in 2005, the second edition of the encyclopedia was completed and published by John Beasley under the title The Classified Encyclopedia of Chess Variants.
The Chess Variant Pages website includes a constantly expanding catalogue of variants.
A few chess variants have been the subject of significant computational analysis. Los Alamos chess, a 6×6 variant, was created in 1956 expressly for computers, its simplicity meant that it was possible for the MANIAC I computer to play it, with a victory over a beginner player the first instance of a computer winning a chess-like game against human opposition. Conversely, Arimaa was developed in 2003 to be deliberately resistant to computer analysis while easy for human players, though computers were able to comprehensively surpass human players by 2015.
While solving chess has not yet been achieved, some variants have been found to be simple enough to be solved though computer analysis. The 5×5 Gardner's Minichess variant has been weakly solved as a draw, and a lengthy analysis of Losing chess managed to weakly solve this as a win for white.
Some chess engines are also able to play a handful of variants, for instance the version of Stockfish implemented on Lichess is able to play King-of-the-hill, Three-check chess, Atomic chess, Horde chess, and Racing Kings. The AI included in Zillions of Games is able to play almost any variant correctly programmed within it to a reasonable standard.
Chess variants have been invented in various fiction. In The Chessmen of Mars author Edgar Rice Burroughs describes Jetan which depicts a war between two races of Martian. Burroughs uses of an appendix to fully define the rules of the game. More commonly specifics of fictional variants aren't detailed in the original works, though several have been codified into playable games by fans. An example of this is Tri-Dimensional Chess from Star Trek. On-screen play was not conducted to any specific rules, but a comprehensive rulebook has been since developed.
Fictional chess variants can involve fantastical or dangerous elements that couldn't be implemented in real life. The Chessmen of Mars describes a form of Jetan where the pieces are human beings and captures are replaced by fights to the death between them. The Doctor Who episode "The Wedding of River Song" depicts "Live Chess", which introduces potentially lethal electric currents into the game.
Many Chess variants, particularly those called Modest variants, can be played with a regular Chess set.
2000 A.D. is a chess variant created by V. R. Parton which employs fairy chess pieces on a 10×10 board. Parton published the variant in his 1972 monograph My Game for 2000 A.D. and After.Apocalypse (chess variant)
Apocalypse is a chess variant invented by C. S. Elliott in 1976. The players each start with two horsemen and five footmen on a 5×5 board. The two sides make their moves simultaneously.
The game was featured in Issue 53 of Games & Puzzles magazine.Capablanca Random Chess
Capablanca Random Chess (CRC) is a chess variant invented by Reinhard Scharnagl in 2004. It combines the piece set and 10×8 board from Capablanca Chess with the permutation idea of Fischer Random Chess (FRC or Chess960). This game won a contest in 2005 held at The Chess Variant Pages to design a variant based upon the theme of the number 10.Chad (chess variant)
Chad is a chess variant for two players created by Christian Freeling in 1979. It is played on an uncheckered 12×12 gameboard with one king and eight rooks per side, where rooks are able to promote to queens.
The inventor's aim was "to create a game of tactical and strategical depth that was both simple and elegant to express the concept of mate—the 'pure' chess game". The game was played for many years at the Fanaat games club in the Netherlands and was featured in the periodical The Gamer 6 in May–June 1982.Chakra (chess variant)
Chakra is a chess variant invented by Christian Freeling in 1980. The uniqueness of Chakra is owed to the invention of a new fairy piece named transmitter. Freeling considered an earlier version of the game as insignificant. "Then one night in the early eighties, Ed [van Zon] and I dreamed up the 'transmitter', a piece consisting of two parts called 'chakras', that would function as a 'portal' for transmitting pieces."
The game was first featured in The Gamer magazine in 1981 (issue 3), resulting in much interest and the sale of many Chakra sets. Chakra is included in 100 Other Games to Play on a Chessboard (1983, 2002) by Stephen Addison.Congo (chess variant)
Congo is a chess variant invented by Demian Freeling in 1982 when he was nearly 8 years old. His father (Dutch abstract games designer Christian Freeling) encouraged him to design a variant using a 7×7 gameboard. Demian was already familiar with chess and xiangqi, and the result blends some features from both. Congo became the second-most popular chess variant at the Fanaat games club in Enschede, the Netherlands.
For his Congo engine, Ed van Zon won "Best of the Zillions" First Contest, Best Chess-Related Category in March 2001.Crazyhouse
Crazyhouse (also known as drop chess, mad chess, reinforcement chess, turnabout chess and schizo-chess) is a chess variant similar to bughouse chess, but with only two players. It effectively incorporates a rule from the game shogi, in which a player can introduce a captured piece back to the chessboard as their own.Diplomat chess
Diplomat chess is a chess variant invented by Carlos Martín-Fuertes in 2003 as a contribution to a Contest to design a chess variant on 43 squares, organised by The Chess Variant Pages. It is played on a circular board with 43 cells, including the center circle which is considered orthogonal and diagonal to every adjacent cell. The game includes a fairy piece called 'diplomat' which instead of capturing can suborn enemy pieces.Dragonfly (chess variant)
Dragonfly (also known as Shuttle Chess or Bird Chess) is a chess variant invented by Christian Freeling in 1983. There are no queens, and a captured bishop, knight, or rook becomes the property of the capturer, who may play it as his own on a turn to any open square. The board is 7×7 squares, or alternatively a 61-cell hexagon with two additional pawns per side.
The game is an offshoot and simplification of a Freeling game named Loonybird (or Dragon Chess). Still, "Play is complex and interesting. Draws are rare too." (Wood 1994:94)Embassy Chess
Embassy Chess is a chess variant created in 2005 by Kevin Hill. It borrows the opening setup from Grand Chess by Christian Freeling and adapts it to the 10x8 board. Embassy chess is a non-commercial Capablanca Random Chess variant that is played on a 10x8 board with two additional pawns per side and two fairy chess pieces: the marshall and the cardinal.
The marshall moves as both a rook and a knight.
The cardinal moves as both a bishop and a knight.The castling in this chess variant is done by king moving 3 spaces in rook direction, see diagram at right. All other rules, like en passant are the same as in chess.Legan chess
Legan chess (or Legan's game) is a chess variant invented by L. Legan in 1913. It differs from standard chess by the starting position as well as by pawn movements.List of chess variants
This is a list of chess variants. Many thousands of variants exist; the 2007 catalogue in The Encyclopedia of Chess Variants estimates that there are well over 2,000, with the author noting that many more known variants were considered too trivial for inclusion. This list includes those variants for which an article exists on the English Wikipedia, as well as some other variants of importance.Losing Chess
Losing Chess (also known as Antichess, the Losing Game, Giveaway Chess, Suicide Chess, Killer Chess, Must-Kill, Take-All Chess, Capture Chess or Losums) is one of the most popular chess variants. The objective of each player is to lose all of their pieces or be stalemated, that is, a misère version. In some variations, a player may also win by checkmating or by being checkmated.
The origin of the game is unknown, but believed to significantly predate an early version, named Take Me, played in the 1870s. Because of the popularity of Losing Chess, several variations have spawned. The most widely played (main variant) is described in Popular Chess Variants by D. B. Pritchard.Modern Chess (chess variant)
Modern Chess is a chess variant played on a 9×9 board. The game was invented by Gabriel Vicente Maura in 1968. Besides the usual set of chess pieces, each player has an additional piece with a corresponding pawn:
The prime minister (M) combines powers of a bishop and a knight.The first match was played in Madrid at Escuela de Bellas Artes de San Fernando's cafe on March 18, 1968. The players were Gabriel Vicente Maura himself (White), and Bonifacio Pedraz Cabezas (Black).Parallel Worlds Chess
Parallel Worlds Chess is a three-dimensional chess variant invented by R. Wayne Schmittberger in the 1980s. The gamespace comprises three 8×8 chessboards at different levels. Each side commands two full chess armies on levels 1 and 3. Level 2 begins empty and obeys its own move rules.Pocket Mutation Chess
Pocket Mutation Chess is a chess variant invented by Mike Nelson in 2003. In this game a player can take a piece from the board and put it into a pocket. The piece in the pocket can be put back on the board later. When placing the piece into the pocket the player can mutate the piece, i.e. change it to a different piece.
The game is one of the Recognized Chess Variants at The Chess Variant Pages.Rollerball (chess variant)
Rollerball is a chess variant invented by Jean-Louis Cazaux in 1998. The game was inspired by the 1975 science-fiction movie Rollerball, specifically the futuristic and violent sport (similar to Roller Derby) portrayed in the film.
The board comprises 7×7 squares with the central 3×3 section missing. Pieces generally move clockwise around the board. Each player starts with one king, one bishop, two rooks, and two pawns.The Chess Variant Pages
The Chess Variant Pages is a popular non-commercial Internet website devoted to chess variants. It was created by Hans Bodlaender in 1995. The site is "run by hobbyists for hobbyists" and is "the most wide-ranging and authoritative web site on chess variants".The site contains a large compilation of games with published rules. The aims of the site are to educate readers about chess variants, encourage gameplay, and provide a place for free discussion. The site has featured game competitions as well as variant design competitions, and provides facilities for publishing documents. Numerous files are available for playing variants using the Zillions of Games proprietary software engine. The site also features The Game Courier software developed by Fergus Duniho which can be used to play almost any variant. There is also an extensive encyclopedia of fairy chess pieces.Other contributing editorial volunteers include (alphabetically by last name): Peter Aronson, Jean-Louis Cazaux, Antoine Fourrière, Ed Friedlander, Ben Good, David Howe, Joe Joyce, Glenn Overby II, Tony Quintanilla, and Peter Spicer. Early editors included John William Brown, Tom Cook, Pavel Tikhomirov, and Vu Q. Vo.Wildebeest Chess
Wildebeest Chess is a chess variant created by R. Wayne Schmittberger in 1987. The Wildebeest board is 11×10 squares. Besides the standard chess pieces, each side has two camels and one wildebeest. The inventor's intent is "to balance the number of 'riders'—pieces that move along open lines—with the number of 'leapers'—pieces that jump". (So for each side, two knights, two camels, and a wildebeest balance two rooks, two bishops, and a queen.)
The game was played regularly in the (now defunct) correspondence game club NOST.