View source for List of chess variants

{{Short description|none}}
{{Use British English|date=August 2012}}
[[File:Hexagonal chess.svg|thumb|upright=1.5|[[Gliński's hexagonal chess]] by Władysław Gliński (1936) was popular in Eastern Europe with a reported half-million players.{{sfnp|Pritchard|1994|p=139|ps=}}]]

This is a list of [[chess variant]]s. Many thousands of variants exist. The 2007 catalogue ''The Encyclopedia of Chess Variants'' estimates that there are well over 2,000, and many more were considered too trivial for inclusion in the catalogue.{{sfnp|Pritchard|2000|p=8|ps=: "Most published ones (but none described here), are, in truth, forgettable."}} 
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== Contemporary chess variants ==
{{Dynamic list}}
The chess variants listed below are derived from chess by changing one or more of the many rules of the game. The rules can be grouped into categories, from the most innocuous (starting position) to the most dramatic (adding chance/randomness to the gameplay after the initial piece placement). If a variant changes rules from multiple categories, it belongs to the sub-section below corresponding to the later-listed category.
* Starting position and armies
* Piece types
* Midgame rules and end-of-game rules
* Board shape
* Number of players
* Use of hidden information or chance

Names that represent a set of variants are annotated with "[multivariant]" after their name. All variants use an 8x8 board unless otherwise specified.

=== Variant starting position (rectangular board, standard piece types and rules) ===
Many variants employ standard chess rules and mechanics, but vary the number of pieces, or their starting positions. 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 [[chess opening|opening]] knowledge. The downside of these variants is that the initial position usually has less harmony and balance than the standard chess position.{{sfnp|Pritchard|2000|p=18}}
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 |'''Upside-down chess''' starting position (White sits at bottom)
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==== Fixed positions ====
* '''Active chess''': Played on a 9×8 board, adding a queen with an extra pawn in front. Invented by G. Kuzmichov (1989), whose students tested the game, deciding that the optimal starting position was to place the second queen on the eighth or ninth files.{{sfnp|Pritchard|2007|p=114}}
* '''[[Displacement chess]]''' [multivariant]: Some pieces in the initial position are exchanged but the rules remain exactly the same. Some examples of this may be that the king and queen are flipped, or the knight on the b-[[file (chess)|file]] is traded with the bishop on the f-file.
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|'''[[Double Chess]]''' by Julian Hayward}}
* '''[[Double chess]]''': Two full armies per side on a 12×16 board, the first to mate an enemy king wins. Pawns advance up to four steps on their first move. [[José Raúl Capablanca|Capablanca]] found the game "remarkably interesting".{{sfnp|Pritchard|1994|p=91|ps=: "Hayward drew Capablanca's attention to the game. The Cuban found it 'remarkably interesting' and a match was arranged between him and the Hungarian master Geza Maroczy."}} Invented by Julian Hayward (1916).
* '''Endgame chess''' (or '''the Pawns Game''', with unknown origins): Players start the game with only pawns and a king. Normal check, checkmate, ''[[en passant]]'', and pawn promotion rules apply.{{sfnp|Pritchard|2007|p=72}}
* '''[[Los Alamos chess]]''' (or '''anti-clerical chess'''): Played on a 6×6 board without bishops. This was the first chess-like game played by a computer program.
* '''Upside-down chess''': The white and black pieces are switched so that White's pieces are on the 8th rank, with pawns on the 7th rank, one step away from promotion. The starting position looks like a standard chess starting position, but from the other player's perspective. As the pawns are blocked by pieces in the starting position, the game always starts with a knight move, and [[smothered mate]]s are common.<ref>[http://www.chessvariants.org/diffsetup.dir/upside.html Upside-down chess] {{Webarchive|url=https://web.archive.org/web/20060618023432/http://www.chessvariants.org/diffsetup.dir/upside.html |date=2006-06-18 }} by [[Hans Bodlaender]]</ref>

==== Player-chosen positions ====
* '''Casablanca chess''': The starting position is chosen from a famous historic game; usually an interesting [[Chess middlegame|middlegame]] position. The position is verified to be approximately equal by a computer, and should have winning chances for both sides.<ref>{{cite web |url=https://www.mcw.ma/_files/ugd/78af52_eae053e1b06c453cb43fb1d00a7f045a.pdf |title=Casablanca variant for website |access-date=20 May 2024 |archive-date=20 May 2024 |archive-url=https://web.archive.org/web/20240520223547/https://www.mcw.ma/_files/ugd/78af52_eae053e1b06c453cb43fb1d00a7f045a.pdf |url-status=live }}</ref> The first Casablanca chess tournament was played in May 2024, and won by [[Magnus Carlsen]].<ref>{{cite web |title=The Tournament |url=https://www.mcw.ma/en/le-tournoi |website=Casablanca-Chess |access-date=20 May 2024 |language=en |archive-date=20 May 2024 |archive-url=https://web.archive.org/web/20240520223546/https://www.mcw.ma/en/le-tournoi |url-status=live }}</ref><ref>{{cite web |last1=Lang |first1=J. J. |title=Learning From the Classics: Takeaways from First Casablanca Variant Tournament in Morocco |url=https://new.uschess.org/news/learning-classics-takeaways-first-casablanca-variant-tournament-morocco |website=US Chess.org |access-date=20 May 2024 |language=en |date=20 May 2024 |archive-date=20 May 2024 |archive-url=https://web.archive.org/web/20240520222203/https://new.uschess.org/news/learning-classics-takeaways-first-casablanca-variant-tournament-morocco |url-status=live }}</ref>
* '''Pre-chess''': The game starts with white and black pawns set as usual, but the initial position of other pieces is selected by the players. White first places one of their pieces on their first rank, and then Black does the same. Players continue to alternate in this manner until all pieces have been placed, with the only restriction being that bishops must be on opposite-colour squares. The game then proceeds in the usual way. Proposed by [[Pal Benko]] in 1978.{{sfnp|Pritchard|2007|p=77}}
* '''Polgar reform chess''' [multivariant]: In his book ''Reform-Chess'' (1997), [[László Polgár]] proposed several variants played on board of size 5×8, 6×8, 8×6, or 9×6.<ref>{{cite book |author=László Polgár |title=Reform-Chess |publisher=Könemann Verlags GmbH |year=1997 |isbn=978-3-89508-226-9|author-link=László Polgár }}</ref> The initial piece setup is determined by players in the same way as in Benko's Pre-chess. There are special rules for [[castling]] depending on the board. Polgár recommended these variants to train creativity and to speed up the game.

==== Random positions ====
{| style="float:right;"  border="0" cellpadding="1" cellspacing="0"
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 |'''[[Chess960]]''', one of the 960 possible starting positions
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* '''[[Fischer Random Chess]]''' (also known as '''Chess960''' and more recently as '''Freestyle Chess'''): The placement of the pieces on the first [[rank (chess)|rank]] is randomized; although there are rules such as the 2 starting Bishops have to be on different colour squares, and the King has to start between the 2 Rooks. The opponent's pieces mirror it. Invented by [[Bobby Fischer]] (1996).
* '''[[Transcendental Chess]]''': Similar to [[Chess960]], but the opening white and black positions do not mirror each other.

==== Unequal armies ====
In these variants, White and Black do not necessarily begin with the same quantities of each piece type (for example, White may begin with more pawns than Black).
* '''[[Dunsany's Chess]]''' (and the similar '''Horde chess'''): One side has standard chess pieces, and the other side has 32 pawns.
* '''[[Chess handicap|Handicap chess]]''' (or '''Chess with odds''') [multivariant]: Variations to equalise chances of players with different strength.
* '''Peasants' Revolt''': White has a king and eight pawns (the peasants) against Black's king, pawn, and four knights (the nobles). Black has the advantage. To narrow the contest, the game has also been played with three knights (on b8, c8, and g8) instead of four. By R. L. Frey (1947).<ref>{{cite web |url=http://www.chessvariants.org/large.dir/peasantrevolt.html |title=Peasant Revolt |last=Whelan |first=George |publisher=[[The Chess Variant Pages]] |date=2003-03-10 |access-date=2014-01-21 |archive-date=2014-02-04 |archive-url=https://web.archive.org/web/20140204041855/http://www.chessvariants.org/large.dir/peasantrevolt.html |url-status=live }}</ref>{{sfnp|Pritchard|2007|p=76}}
* '''Sixteen Pawns''': White plays without their queen, but chooses where on the third and fourth ranks to place eight extra pawns. By [[Legall de Kermeur]] (18th century). [[Alexandre Deschapelles]] and [[Louis-Charles Mahé de La Bourdonnais]] later established that eight extra pawns favour White too much, and hence played the game with only five, six, or seven extra pawns for White instead.<ref>{{cite web | url=http://www.chessvariants.com/unequal.dir/16pawns.html | title=Sixteen Pawns | access-date=2017-12-22 | archive-date=2017-12-22 | archive-url=https://web.archive.org/web/20171222105938/http://www.chessvariants.com/unequal.dir/16pawns.html | url-status=live }}</ref>
* '''[[Really Bad Chess]]''': A [[mobile video game]] by [[Zach Gage]]; Each player has one king and fifteen other pieces selected at random. 
* '''Weak!''': White has the usual pieces, Black has one king, seven knights, and sixteen pawns. This game was played at a Columbia University chess club in the 1960s.<ref>[http://www.chessvariants.org/unequal.dir/weak.html Weak!] {{Webarchive|url=https://web.archive.org/web/20060307011958/http://www.chessvariants.org/unequal.dir/weak.html |date=2006-03-07 }} by [[Hans Bodlaender]]</ref>

{| style="float:left;"  border="0" cellpadding="1" cellspacing="0"
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 |'''[[Dunsany's Chess]]''' by Lord Dunsany
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=== Variants with fairy chess pieces ===
{{See also|Fairy chess piece}}

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 |'''[[Raumschach]]''' starting position. Inverted knights represent unicorns.
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 |'''Shako''' starting position. Cannons (shown as inverted rooks) are on a1, j1, a10, and j10. Elephants (shown as inverted bishops) are on a2, j2, a9, and j9.
}}
{{col-float-end}}

==== Variants with fairy pieces on a standard board ====
Most of the pieces in these variants are borrowed from chess. The game goal and rules are also very similar to those in chess; however, these variants include one or more [[fairy pieces]] which move differently from chess pieces.
* '''[[Baroque chess]]''' (or '''Ultima'''): Pieces on the first row move like queens, and pieces on the second row move like rooks. They are named after their unusual capturing methods. For example, leaper, immobilizer and coordinator.
* '''[[Berolina chess]]''': All pawns are replaced with Berolina pawns, that move diagonally and capture orthogonally.
* '''[[Chess with different armies]]''': Two sides use different sets of fairy pieces. There are several armies of approximately equal strength to choose from including the standard FIDE chess army.
* '''[[Falcon-Hunter Chess]]''': A falcon moves forward as a bishop; backward as a rook. The hunter moves forward as a rook; backward as a bishop. Players introduce the fairies as the game progresses. By Karl Schulz (1943).
* '''[[Grasshopper chess]]''' [multivariant]: The pawns can promote to grasshopper, or grasshoppers are on the board in the initial position.
* '''[[Pocket Mutation Chess]]''': Player can put a piece temporarily into the pocket, optionally mutating it into another (including fairy) piece.
* '''Spartan chess''': Black (the Spartans) has an army headed by two kings, which otherwise consists exclusively of non-standard pieces, and battles the standard FIDE army (the Persians) of white.<ref>http://spartanchessonline.com/ {{Webarchive|url=https://web.archive.org/web/20160505003528/http://spartanchessonline.com/ |date=2016-05-05 }} by Steven Streetman.</ref>
*'''Super X Chess''': Players can combine their own pieces by capturing them. King or queen can't combine. A combined piece has the ability to move as both pieces that got combined. Same kind of pieces can combine into new pieces. Pieces can't uncombine or combine again.  By Miika Pihkala (2018).<ref>{{cite web|url=https://linuxgameconsortium.com/linux-gaming-news/super-x-chess-releases-tomorrow-steam-linux-70820/|title=Super X Chess releases tomorrow on Steam|date=2018-10-23|website=Linux Game Consortium|access-date=2019-01-07|archive-date=2019-01-07|archive-url=https://web.archive.org/web/20190107234543/https://linuxgameconsortium.com/linux-gaming-news/super-x-chess-releases-tomorrow-steam-linux-70820/|url-status=live}}</ref>
* '''Torpedo chess''': Pawns are replaced with torpedo pawns, which can move two squares forwards anywhere on the board as opposed to only on the first move. Pawns that move two squares can be captured ''en passant'' on the very next move. The rest of the pieces remain unchanged.<ref>{{Citation | arxiv=2009.04374 | title=Assessing Game Balance with AlphaZero: Exploring Alternative Rule Sets in Chess | year=2020 | first1=Nenad | last1=Tomašev | first2=Ulrich | last2=Paquet | first3=Demis | last3=Hassabis | first4=Vladimir | last4=Kramnik}}</ref>
* {{Anchor|Way of the Knight}}'''Way of the Knight''' (WOTN): Invented by [[Ralph Betza]], incorporating two elements from [[tabletop role-playing game]]s. Begins with the standard starting position and pieces, however through capturing and advancing up the board pieces can earn "[[Experience point|experience]]", and a sufficiently experienced piece is upgraded to a more powerful one. Upgrades include various fairy pieces, and involve player choices of "[[Alignment (role-playing games)|alignment]]".<ref>{{cite web|url=http://www.chessvariants.com/crossover.dir/wotn.html|title=Way of the Knight|website=chessvariants.com|access-date=2018-08-03|archive-date=2018-08-03|archive-url=https://web.archive.org/web/20180803134715/http://www.chessvariants.com/crossover.dir/wotn.html|url-status=live}}</ref><ref>{{cite web|url=http://www.chessvariants.com/crossover.dir/wotnsample.html|title=A Sample game of Way of the Knight|last=Trenholme|first=Sam|website=chessvariants.com|access-date=2018-08-03|archive-date=2018-08-03|archive-url=https://web.archive.org/web/20180803134556/http://www.chessvariants.com/crossover.dir/wotnsample.html|url-status=live}}</ref>

==== Variants with popular fairy pieces: Empress, Amazon, Princess ====
There are a number of variants which use the [[Empress (chess)|empress]] (rook + knight) and [[Princess (chess)|princess]] (bishop + knight) compound pieces. The empress is also called marshall or chancellor.<ref>[http://www.chessvariants.org/piececlopedia.dir/rook-knight.html The Piececlopedia: The Rook-Knight Compound] {{Webarchive|url=https://web.archive.org/web/20151117121137/http://www.chessvariants.org/piececlopedia.dir/rook-knight.html |date=2015-11-17 }} by Fergus Duniho and David Howe.</ref> The princess is also called cardinal, archbishop, janus, paladin, or minister.<ref>[http://www.chessvariants.org/piececlopedia.dir/bishop-knight.html The Piececlopedia: Bishop-Knight Compound] {{Webarchive|url=https://web.archive.org/web/20151117141127/http://www.chessvariants.org/piececlopedia.dir/bishop-knight.html |date=2015-11-17 }} by Fergus Duniho and David Howe.</ref> Another compound piece is the [[Amazon (chess)|amazon]] (queen + knight). To adapt to the new pieces, the board is usually extended to 10×8 or 10×10 with additional pawns added.<ref name="material power in variant chess games">{{Cite web|url=https://www.chess.com/forum/view/chess960-chess-variants/comparison-of-material-power-in-variant-chess-games|title=Comparison of Material Power in Variant-Chess Games - Chess Forums|website=Chess.com|access-date=2017-12-21|archive-date=2017-12-22|archive-url=https://web.archive.org/web/20171222051714/https://www.chess.com/forum/view/chess960-chess-variants/comparison-of-material-power-in-variant-chess-games|url-status=live}}</ref>
* '''[[Almost Chess]]''': Uses an 8×8 board, with the conventional starting position, but queens are replaced by chancellors (empresses). By Ralph Betza (1977). A related variant is '''[[Sort of Almost Chess]]''' (Ralph Betza, 1994), where one player has a queen and the other has a chancellor.
{{Chess diagram 10x10
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|fen=r8r/1nbqkcabn1/pppppppppp/10/10/10/10/PPPPPPPPPP/1NBQKCABN1/R8R
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'''[[Grand Chess]]''' by Christian Freeling}}
* '''[[Capablanca Chess]]''': A variant by the former world chess champion, [[José Raúl Capablanca]]. Played on a 10×8 board with chancellor (empress) and archbishop (princess).
* '''[[Capablanca Random Chess]]''': Generalises all possible variants of [[Capablanca Chess]] with random starting positions following a method similar to that used in [[Chess960]]. By Reinhard Scharnagl (2004). 
* '''[[Grand Chess#Embassy chess|Embassy Chess]]''': Uses a 10×8 board with Marshall (Empress) and Cardinal (Princess). The starting position is borrowed from [[Grand Chess]]. By Kevin Hill (2005).
*'''Gemini Chess''':<ref>{{Cite web|url=https://musketeerchess.net/games/gemini/rules/rules.php|title=Gemini Chess Variant|date=2016|website=Musketeer Chess and Chess Variants|access-date=2017-11-27|archive-date=2017-09-06|archive-url=https://web.archive.org/web/20170906191142/http://musketeerchess.net/games/gemini/rules/rules.php|url-status=live}}</ref> Uses a 10×8 board with two Archbishops. From an idea of Dr Zied Haddad in 2016. The difference from Janus Chess is the initial setup where the archbishops are sandwiching the queen and king remaining in the center of the board. 
{{Chess diagram 8x10
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|Gemini Chess initial position. The archbishops surround the queen and king from each side
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* '''[[Capablanca chess#Postdating Capablanca chess|Gothic chess]]''': A commercial variant played on a 10×8 board with Chancellor (Empress) and Archbishop (Princess).
* '''[[Grand Chess]]''': Uses a 10×10 board with marshall (empress) and cardinal (princess). Invented by [[Christian Freeling]] (1984).
* '''[[Janus Chess]]''': Uses a 10×8 board with two januses (princesses). By Werner Schöndorf (1978).
* '''[[Maharajah and the Sepoys]]''': Black has a complete army, and White only one piece: the maharajah (a royal amazon).
* '''[[Modern Chess (chess variant)|Modern Chess]]''': Played on a 9×9 board, with an extra pawn and a prime minister (princess). By Gabriel Vicente Maura (1968).
*'''{{vanchor|Musketeer chess}}''':<ref>{{Cite web|url=https://www.musketeerchess.net/|title=Musketeer Chess, a modern Chess Variant|website=Musketeer Chess & Chess Variants|access-date=2019-11-18|archive-date=2016-07-20|archive-url=https://web.archive.org/web/20160720011155/http://musketeerchess.net/|url-status=live}}</ref> A commercial variant, inspired from [[Seirawan Chess]]. This variant introduces 10 fairy pieces: archbishop, chancellor, hawk (different rules from Seirawan Chess), elephant (different rules from Seirawan Chess), leopard, cannon (different from Xiangqi), unicorn, fortress, spider, and amazon (also called dragon in this game). Players have a choice of 2 pieces among the 10 possible and method used to introduce them during the game.
* '''[[Seirawan Chess]]''': A commercial variant. Uses a standard 8×8 board with elephant (empress) and hawk (princess).<ref>{{Cite web|url=http://www.seirawanchess.com/|title=Seirawan chess {{pipe}} Yasser Seirawan|website=seirawanchess.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622045140/http://seirawanchess.com/|url-status=live}}</ref> By [[Grandmaster (chess)|GM]] [[Yasser Seirawan]] and [[Bruce Harper]] (2007).

==== Other variants with fairy pieces ====
* '''[[2000 A.D. (chess variant)|2000 A.D.]]''': Played on a 10×10 board, features the empress, capricorn, gorgon, chimaera, dragon, minotaur, unicorn, and fury fairy chess pieces. By V. R. Parton.
* '''Bear chess''':<ref name="chessvariants_bearchess">[https://www.chessvariants.com/rules/bear-chess About Bear chess] {{Webarchive|url=https://web.archive.org/web/20210612153941/https://www.chessvariants.com/rules/bear-chess |date=2021-06-12 }} on chessvariants.com.</ref><ref name="evochess_bearchess">[https://www.evochess.com/chess-variant/bear/ About Bear chess] {{Webarchive|url=https://web.archive.org/web/20220705220920/https://www.evochess.com/chess-variant/bear/ |date=2022-07-05 }} on evochess.com.</ref><ref name="encyclopedia_chess_variants">[http://www.jsbeasley.co.uk/encyc.htm Chapter 15, New pieces (2) : Pieces with limited range (pages 128—137)] {{Webarchive|url=https://web.archive.org/web/20210615035121/http://www.jsbeasley.co.uk/encyc.htm |date=2021-06-15 }} from The Classified Encyclopedia of Chess Variants (D. B. Pritchard, ISBN 978-0-9555168-0-1, 2007).</ref> 10x10 [[chess variant]], proposed by Mikhail Sosnovsky in 1985 in [[Tver|Kalinin]].<ref name="kp_bearchess">[https://www.tver.kp.ru/daily/27284.5/4420333/ «Медвежьи шахматы могут подвинуть тверского козла»] {{Webarchive|url=https://web.archive.org/web/20210612154233/https://www.tver.kp.ru/daily/27284.5/4420333/ |date=2021-06-12 }} — article in Komsomolskaya Pravda (in Russian)</ref><ref name="mk_bearchess">[https://tver.mk.ru/social/2021/06/02/shakh-i-mat-skeptiki-zapadnye-shakhmatisty-ocenili-tverskoy-apgreyd.html Шах и мат, скептики: западные шахматисты оценили тверской апгрейд] {{Webarchive|url=https://web.archive.org/web/20210612154234/https://tver.mk.ru/social/2021/06/02/shakh-i-mat-skeptiki-zapadnye-shakhmatisty-ocenili-tverskoy-apgreyd.html |date=2021-06-12 }} — article in Moskovskij Komsomolets (in Russian)</ref> Board 10x10; extra pieces are Bears, which leap as N or two squares as R or B; baseline (a1-j1/a10-j10) RNBBeQKBeBNR. Pawns can move up to three squares initially (e.p. permitted). In castling, K moves to c/h files.
* '''Chessers''': There are multiple variants that combine the rules of chess and [[Draughts|checkers]], including a 1925 variant by Frank Maus,<ref name="encyclopedia_chess_variants_18">[http://www.jsbeasley.co.uk/encyc.htm Chapter 18, Mutation games (pages 161—174)]{{Webarchive|url=https://web.archive.org/web/20210615035121/http://www.jsbeasley.co.uk/encyc.htm |date=2021-06-15 }} from The Classified Encyclopedia of Chess Variants (D. B. Pritchard, ISBN 978-0-9555168-0-1, 2007).</ref> and a 1960 proprietary variant by Phillips Publishers, Inc.<ref name="encyclopedia_chess_variants_15">[http://www.jsbeasley.co.uk/encyc.htm Chapter 15, New pieces (2) : Pieces with limited range (pages 128—137)] {{Webarchive|url=https://web.archive.org/web/20210615035121/http://www.jsbeasley.co.uk/encyc.htm |date=2021-06-15 }} from The Classified Encyclopedia of Chess Variants (D. B. Pritchard, ISBN 978-0-9555168-0-1, 2007).</ref>
* '''[[Chess on a really big board]]''': Played on a 16x16 board with 6 nonstandard piece types. Invented by Ralph Betza.
* '''Decimal Chess''' [multivariant]: Played on a 10×10 board, usually add extra pieces. Some decimal chesses use only standard pieces, but others such as [[Decimal Falcon-Hunter Chess]] use fairy pieces. One such variant is '''Decimal Rettah chess''', which adds a king, queen and two pawns. Invented by [[V. R. Parton]]. 
*'''[[Dragonchess]]''': Three 8x12 boards with some standard chess pieces and many other pieces, some of which move between the levels. Created by Gary Gygax.<ref>{{Cite web |title=Dragonchess - rules |url=https://www.chessvariants.com/3d.dir/dragonchess.html |access-date=2022-04-20 |website=chessvariants.com |archive-date=2022-04-27 |archive-url=https://web.archive.org/web/20220427040630/https://www.chessvariants.com/3d.dir/dragonchess.html |url-status=live }}</ref>
*'''[[Duell (chess)|Duell]]''': Dice are used instead of pieces. Played on a 9×8 board.
* '''Etchessera''': Played on a regular chessboard but where players build their own chess army from a collection of 17 different pieces.<ref>{{Cite web|url=http://etchessera.com/|title=Etchessera|access-date=2021-12-26|archive-date=2022-03-27|archive-url=https://web.archive.org/web/20220327082742/http://www.etchessera.com/|url-status=live}}</ref>
*'''[[Gess]]''': Chess with variable pieces, played on a [[Go (game)|Go]] board.
* '''[[Jetan]]''': A "Martian chess" invented by [[Edgar Rice Burroughs]] for his novel ''[[The Chessmen of Mars]]'' (1922), played on a 10×10 board. None of the pieces are standard chess pieces.<ref name="ekman">{{cite web |last1=Ekman |first1=Fredrik |title=Exploring Jetan |url=http://www.erbzine.com/mag70/7030.html |website=ERBzine |publisher=Bill Hillman |access-date=5 January 2020 |archive-date=25 December 2019 |archive-url=https://web.archive.org/web/20191225232847/http://www.erbzine.com/mag70/7030.html |url-status=live }}</ref>
* '''Prince & Princess''': The chess variant that uses the criterion of succession, where the king or queen are replaced in favor of the prince or the princess, created by [[Antonio Maravi Oyague]].<ref>{{Cite web |last=Oyague |first=Antonio Maravi |date=July 22, 2015 |title=CHESS 10X10 SUCCESSION PRINCE PRINCESS SUCESION PRINCIPES FAMILIAR |url=http://profemaravi.blogspot.com/2015/07/chess-10x10-succession-prince-princess.html |url-status=dead |archive-url=https://web.archive.org/web/20180917105136/http://profemaravi.blogspot.com/2015/07/chess-10x10-succession-prince-princess.html |archive-date=September 17, 2018 |website=Profe Antonio Maravi}}</ref>
* '''Proteus''': A chess variant using dice to represent normal chess pieces, created by [[Steve Jackson Games]].{{sfnp|Pritchard|2007|p=304}}
* '''Shako''': Played on a 10×10 board. New pieces are the cannon from [[xiangqi]] (Chinese chess) and an elephant moving as a fers+alfil of old [[shatranj]] (ancestors of queen and bishop), so diagonally one or two squares with jumps allowed. By Jean Louis-Cazaux (1997).<ref>[http://www.chessvariants.org/large.dir/shako.html Shako] {{Webarchive|url=https://web.archive.org/web/20101207013023/http://chessvariants.org/large.dir/shako.html |date=2010-12-07 }} by [[Hans Bodlaender]]</ref>
* '''[[Stealth chess]]''': Played in the fictional [[Ankh-Morpork Assassins' Guild]] from the ''[[Discworld]]'' series of books; played on an 8×10 board. The fairy piece is the [[Games of the Discworld#Stealth Chess|Assassin]].
* '''[[Stratomic]]''': Adds nuclear missiles to the standard chess array on a 10×10 board. When launched they irradiate any 3×3 area (friendly pieces included) except kings. By Robert Montay-Marsais (1972). 
* '''[[Wildebeest Chess]]''': Uses an 11×10 board, each player has two camels and a wildebeest (camel + knight). Pawns move one, two, or three squares initially. By R. Wayne Schmittberger (1987). 
* '''[[Wolf Chess]]''': On an 8×10 board, with fairy pieces wolf (empress), fox (princess), [[Nightrider (chess)|nightrider]], sergeant (almost a [[Berolina chess|Berolina pawn]]), and elephant (amazon). By Arno von Wilpert (1943).

=== Variant rules ===
These variants introduce changes in the mechanics of the game, such as movement of pieces, rules for capturing, or winning conditions.
==== Standard board ====
* '''65th case''': a 65th optional case is available adjacent to the board. Other rules remain the same.

==== Variant move counts ====
In these variants one or both players can move more than once per turn. The board and the pieces in these variants are the same as in standard chess.
* '''[[Avalanche chess]]''': Each move consists of a standard chess move followed by a move of one of the opponent's pawns.
* '''Double-Move Chess''': Similar to '''Marseillais chess''', but with no ''[[en passant]]'', check, or checkmate. The objective is to capture the king. By [[Fred Galvin]] (1957).<ref>{{Cite web|url=https://www.chessvariants.com/multimove.dir/doublemove.html|title=Doublemove chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-03-24|archive-url=https://web.archive.org/web/20190324160153/https://www.chessvariants.com/multimove.dir/doublemove.html|url-status=live}}</ref>
* '''Double-Take Chess''': Each player, once per game, can make two moves during one of their turns. These two moves cannot be used to place the opponent's king in checkmate.<ref>[https://jmar306.wordpress.com/wp-admin/post.php?post=36&action=edit&message=6&postpost=v2 Double-Take Chess] by Joel Marler</ref>
* '''[[Kung-fu chess]]''': A variant without turns. Any player can move any of their pieces at any given moment.
* '''[[Marseillais chess]]''' (or '''Two-move chess'''): After the first turn of the game by White being a single move, each player moves twice per turn.
* '''[[Monster chess]]''' (or '''Super King'''): White has the king and four pawns (c2-f2) against the entire black army but may make two successive moves per turn. There is no check. Players win by capturing the king. In a variant, White's pieces begin one row forward of their usual starting position, and the White's pawns may not begin with a double step. Another variant denies Black promotion rights (pawns reaching the last rank remain as pawns). White may always promote.
*'''Multimove Chess (''i'', ''j'')''': A class of chess variants where white gets ''i'' moves per turn and black gets ''j'' moves per turn. Check is not enforced, and victory is by capturing the enemy king. The games are described and analysed logically in a 2015 journal article. The authors [[solved game|weakly solved]] the game for all (''i'', ''j'') pairs except for (1, 1) (functionally, regular chess) and (2, 2).<ref>{{cite journal |last1=Berger |first1=Emily Rita |last2=Dubbs |first2=Alexander |title=Winning Strategies in Multimove Chess (''i'', ''j'') |journal=Journal of Information Processing |date=2015 |volume=23 |issue=3 |pages=272–275 |doi=10.2197/ipsjjip.23.272|arxiv=1403.6154 |s2cid=34207664 }}</ref>
*'''[[Progressive chess]]''' (or '''Scottish chess'''): White moves once, then Black moves twice, then White moves three times, and so on.
* '''Swarm chess''': During each turn, each piece that a player can move must be moved.<ref>{{Cite web|url=https://www.youtube.com/watch?v=tUjqIuKumI0| archive-url=https://ghostarchive.org/varchive/youtube/20211118/tUjqIuKumI0| archive-date=2021-11-18 | url-status=live|title=Chess: Swarm Variation|date=September 13, 2017|via=YouTube}}{{cbignore}}</ref>

==== Other variant midgame rules ====
These variants feature variant rules in the middle of the game, but the end goal remains the same (to checkmate the enemy king).
* '''Absorption chess''' (also called '''cannibal chess''', '''power absorption chess''', or '''seizer's chess'''): Pieces gain the abilities of the pieces they capture.<ref>{{cite web|url=http://www.chessvariants.com/difftaking.dir/cannibal.html|title=Cannibal Chess and Absorption Chess|access-date=2018-07-02|archive-date=2018-07-02|archive-url=https://web.archive.org/web/20180702181002/http://www.chessvariants.com/difftaking.dir/cannibal.html|url-status=live}} ''[[The Chess Variant Pages]]''</ref><ref>{{cite web |url=http://chess.computerwebservices.net/power.php |title=Power Absorption Chess |author=<!--Not stated--> |website=Chess Variants |publisher=Computer Web Services |access-date=2018-07-06 |archive-date=2018-07-07 |archive-url=https://web.archive.org/web/20180707011145/http://chess.computerwebservices.net/power.php |url-status=live }}</ref>
* '''[[Andernach chess]]''': A piece making a capture changes colour.
* '''ASEAN chess''': Pawns start on the 3rd ranks. Queens can only move 1 square diagonally and Bishops only 1 square diagonally or 1 square directly forward.<ref>{{Cite web |last=Roebuck |first=Matt |date=2016-12-27 |title=ASEAN Chess: making a move |url=https://medium.com/matt-roebuck/asean-chess-making-a-move-cb7b89ffd4cb |access-date=2022-08-25 |website=Matt Roebuck |archive-date=2022-08-25 |archive-url=https://web.archive.org/web/20220825104855/https://medium.com/matt-roebuck/asean-chess-making-a-move-cb7b89ffd4cb |url-status=live }}</ref>
* '''[[Atomic chess]]''': Capture on any square results in an "atomic explosion" which kills (i.e. removes from the game) all pieces in the eight surrounding squares, except for pawns.
* '''Benedict chess''': Instead of capturing by displacement, players may convert an enemy piece they attack to their own color.<ref>{{Cite web|url=https://www.chessvariants.com/difftaking.dir/benedict.html|title=Benedict Chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050241/https://www.chessvariants.com/difftaking.dir/benedict.html|url-status=live}}</ref>

{{Chad diagram
| tright
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|  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |rd|rd|rd|  |
|  |  |  |  |  |  |  |rd|kd|rd|  |
|  |  |  |  |  |  |  |rd|rd|rd|  |
|  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  | |  |  |  |  |  |  |
|  |  |rl|rl|rl|  |  |  |  |  |  |
|  |  |rl|kl|rl|  |  |  |  |  |  |
|  |  |rl|rl|rl|  |  |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |  |  |  |  |
|''[[Chad (chess variant)|Chad]]'' by Christian Freeling
}}
* '''[[Chad (chess variant)|Chad]]''': Kings are limited to 3×3 "castles" on a 12×12 board dominated by eight rooks per side which can promote to queens. By Christian Freeling (1979).
* '''Checkers chess''': Pieces can only move forward until they have reached the far rank.{{sfnp|Pritchard|2007|p=51}}
* '''[[Checkless chess]]''': Players are forbidden from giving [[check (chess)|check]] except to [[checkmate]].
* '''[[Chessplus]]''': Commercial variant. Up to two of any friendly pieces (except the king) may occupy the same single square. Either piece may choose to carry the other with it if or when it moves.<ref>{{Cite web |title=Chessplus - It's Not Chess. It's Better. |url=https://www.chessplus.com/ |access-date=2022-08-25 |website=Chessplus |archive-date=2022-08-25 |archive-url=https://web.archive.org/web/20220825104856/https://www.chessplus.com/ |url-status=live }}</ref>
* '''[[Circe chess]]''': Captured pieces are reborn on their starting squares.
* '''[[Congo (chess variant)|Congo]]''': Kings (lions) are limited to 3×3 "castles" on a 7×7 board. By Demian Freeling (1982). 
* '''[[Crazyhouse]]''': Captured pieces change color to match the capturing player’s pieces and can be returned to any unoccupied square on a later turn. There are two variations of this variant, known as '''Loop Chess''' and '''Chessgi'''. 
* '''[[Cubic Chess]]''': Piece cubes display the six piece types; a player can promote any pawn by rotating its cube to match a captured piece type. By Vladimír Pribylinec (1977).
* '''[[Dragonfly (chess variant)|Dragonfly]]''': Played on a 7×7 or with a hexagonal board, no queens, captured non-pawn pieces never die (à la Chessgi) and can be dropped on any open square. By Christian Freeling.
* '''[[Dynamo Chess]]''': Capturing is replaced by pushing or pulling enemy pieces off the board. By Hans Klüver and Peter Kahl (1968). A close variant of '''Push Chess''' (by [[Fred Galvin]], 1967).{{sfnp|Pritchard|2007|pp=66&ndash;67}}
* '''Einstein chess''': Pieces transform into more or less powerful pieces when they move.<ref>{{cite web| url = http://www.janko.at/Retros/Glossary/Einstein.htm| title = Einstein chess| access-date = 2008-05-07| archive-date = 2008-06-10| archive-url = https://web.archive.org/web/20080610132102/http://janko.at/Retros/Glossary/Einstein.htm| url-status = live}}</ref>
* '''Gravity chess''': After every turn, all pieces other than pawns fall towards the higher ranks of the board, until they either reach the eighth rank, or another piece or pawn in the way.<ref>{{Cite web |title=Gravity Chess! |url=https://gravity-chess.andrew.gr/simple/ |access-date=2022-07-27 |website=gravity-chess.andrew.gr |archive-date=2022-07-26 |archive-url=https://web.archive.org/web/20220726130019/http://gravity-chess.andrew.gr/simple/ |url-status=live }}</ref><ref>{{Cite news |author1=Tyler Wilde |date=2019-08-09 |title=This confounding game is chess, but with gravity |work=PC Gamer |url=https://www.pcgamer.com/this-confounding-game-is-chess-but-with-gravity/ |access-date=2022-07-30 |archive-date=2022-07-27 |archive-url=https://web.archive.org/web/20220727182643/https://www.pcgamer.com/this-confounding-game-is-chess-but-with-gravity/ |url-status=live }}</ref>
* '''[[Grid chess]]''': The board is overlaid with a grid of lines. For a move to be legal, it must cross at least one of these lines.
* '''Guard chess''' (or '''Icelandic chess'''): Allows captures only when a piece is completely unprotected by friendly pieces. Checkmate occurs when the piece forcing the mate is protected and therefore cannot be captured.<ref>{{Cite web|url=https://www.chessvariants.com/difftaking.dir/guardchess.html|title=Guard Chess, or Islandic Chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050215/https://www.chessvariants.com/difftaking.dir/guardchess.html|url-status=live}}</ref>
* '''Haft Schrödinger Chess''': Every piece starts in a [[quantum superposition]] initially able to be any piece until the waveform is collapsed by observation. As in chess, Haft Schrödinger Chess does not have [[Perfect information#Examples|hidden information]], whereas Schrödinger's Chess is regarded as a game of hidden information. A digital implementation of the game exists called Entanglement Chess. <ref>{{Cite web|url=http://antumbrastation.com/haft-schroedinger-chess.html|title=Antumbra Station {{pipe}} Haft Schroedinger Chess|website=antumbrastation.com|access-date=2017-12-08|archive-date=2017-12-09|archive-url=https://web.archive.org/web/20171209044840/http://antumbrastation.com/haft-schroedinger-chess.html|url-status=live}}</ref><ref>{{Cite web|url=https://entanglement-chess.netlify.app/index.html|title=Entanglement Chess (HSC)|access-date=2023-01-18|archive-date=2023-01-18|archive-url=https://web.archive.org/web/20230118063340/https://entanglement-chess.netlify.app/index.html|url-status=live}}</ref>
* '''Hierarchical chess''': Pieces must be moved in the order: pawn, knight, bishop, rook, queen, king. A player who has the corresponding piece but cannot move it loses.{{sfnp|Pritchard|2007|p=48}}
* '''[[Hostage chess]]''': Captured pieces are held in the capturer's "prison", and can be released by the opponent and dropped into play (like shogi) via a "hostage exchange". By [[John A. Leslie|John Leslie]] (1997). 
* '''Jedi Knight chess''': Knights may move three steps diagonally or horizontally or both, depending on the rules accepted.<ref>[http://gotjustice.wordpress.com/2007/10/19/jedi-knight-chess-variant/ Jedi Knight chess] {{Webarchive|url=https://web.archive.org/web/20160118074134/https://gotjustice.wordpress.com/2007/10/19/jedi-knight-chess-variant/ |date=2016-01-18 }}.</ref>
{{Chess diagram|clear=right
 |tright
 |
 |rd| | |qd| |rd|kd|
 |pd| | | |bd|nl|pd|pd
 | |pd| | |bl|nd | | 
 | | |pd | | | | | 
 | | | | | | | | 
 | | | | | | | | 
 |pl|pl|pl| | |pl|pl|pl
 |rl| | | |rl| |kl|
 |'''Jump Chess''' example checkmate
}}
* {{Anchor|Jump Chess}}'''Jump chess''': The rook, bishop and queen may move from one side of any piece (friend or foe) to the other side in their normal direction of movement. No change for the King and Knight. Jump move is exactly two squares, and can be used to give check or to capture. Jump moves are notated using '^'. In the starting position, 1.R^a3 and 1.B^a3 are both legal. By former Pentamind<ref>{{cite web | url=https://mindsportsolympiad.com/pentamind-world-championship/ | title=Pentamind World Championship – Mind Sports Olympiad | access-date=2024-02-26 | archive-date=2024-02-26 | archive-url=https://web.archive.org/web/20240226104234/https://mindsportsolympiad.com/pentamind-world-championship/ | url-status=live }}</ref> champion Alain Dekker (2004).<ref>http://www.mayhematics.com/v/vol8/vc59.pdf {{Webarchive|url=https://web.archive.org/web/20220830190112/http://www.mayhematics.com/v/vol8/vc59.pdf |date=2022-08-30 }} {{Bare URL PDF|date=September 2022}}</ref>
* '''Kamikaze chess''' (or '''Hara-Kiri chess'''): When capturing, the capturing piece is removed from play also. This means a king cannot defend itself by capturing an attacker. A capture is not allowed if it exposes one's own king to [[Discovered attack|discovered check]]. Idea from B. G. Laws (1928).{{sfnp|Pritchard|2007|p=44}} The king is royal and removing a check takes precedence over capturing. The king must be lost last; moving into check is permitted after all other pieces have been captured.
* '''[[Knight relay chess]]''': Pieces defended by a friendly knight can move as a knight.
* '''[[Legan chess]]''': Played as if the board would be rotated 45°, initial position and pawn movements are adjusted accordingly.
* '''[[Madrasi chess]]''' (or '''Weird chess'''): A piece which is attacked by the same type of piece of the opposite color is paralysed.
* '''[[Monochromatic chess]]''': All pieces must stay on the same color square as they initially begin.
* '''[[No Castling Chess]]''': standard rules except that castling is not allowed, which means king safety is reduced. Proposed in 2019 by [[Vladimir Kramnik]] with the aim of reducing draws and uninteresting games, and tested on [[Alpha Zero]].[https://www.chess.com/article/view/no-castling-chess-kramnik-alphazero]
* '''[[Patrol chess]]''': Captures and checks are only possible if the capturing or checking piece is guarded by a friendly piece.
* '''[[PlunderChess]]''': The capturing piece is allowed to temporarily take the moving abilities of the piece taken.
* '''Pocket Knight Chess''' (or '''Tombola Chess'''): Players have an extra knight they keep at the side of the board. Once during the game, a player may place the knight on any empty square for their move. Play then proceeds as normal.<ref>{{cite web| url = http://www.chessvariants.com/other.dir/pocket.html| title = "Pocket Knight"| access-date = 2012-02-05| archive-date = 2011-12-14| archive-url = https://web.archive.org/web/20111214130850/http://www.chessvariants.com/other.dir/pocket.html| url-status = live}} ''[[The Chess Variant Pages]]''</ref>{{sfnp|Pritchard|2007|p=52}}
* '''[[Portal Chess]]''' [multivariant]: Any of a number of games that involve pieces or squares for teleportation around the board(s).
* '''Refusal chess''' (or '''Outlaw chess''', '''Rejection chess'''): A played move can be refused by the opponent, forcing the first player to change to another move, which must be accepted.{{sfnp|Pritchard|2007|p=61}}
* '''Replacement chess''' (or Bhagavathi Chess, Canadian Chess, Madhouse Chess, or Repeating Chess): Captured pieces are not removed from the board but relocated by the captor to any vacant square.<ref>{{Cite web|url=https://www.chessvariants.com/difftaking.dir/replacement.html|title=Replacement Chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050213/https://www.chessvariants.com/difftaking.dir/replacement.html|url-status=live}}</ref>
* '''Rifle chess''' (or '''Shooting chess''', '''Sniper chess'''): When capturing, the capturing piece remains unmoved on its original square, instead of occupying the square of the piece captured.<ref>{{Cite web|url=https://www.chessvariants.com/difftaking.dir/rifle.html|title=Rifle Chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050255/https://www.chessvariants.com/difftaking.dir/rifle.html|url-status=live}}</ref> 
* '''{{vanchor|Sovereign Chess|text=Sovereign Chess}}''': This variant is played on a 16×16 board. In addition to the standard black and white pieces, the board is also encircled by 80 other coloured pieces (10 colours of 8 pieces each). Coloured squares near the center of the board correspond to the coloured pieces around the board, and when a player's piece occupies a coloured square, that player gains control of the matching coloured pieces. If a piece on a coloured square is moved or captured, control of the matching pieces is lost (transferred to the other player in case of capture). Players may also switch the color of their initial army through "regime change". By Mark Bates.<ref>{{cite web |last1=Mason |first1=Dave |title=Extreme Chess—Carpinteria resident's game allows players to control extra armies |url=http://www.newspress.com/Top/Article/article.jsp?Section=LIFE&ID=567295907079520299&Archive=true |archive-url=https://web.archive.org/web/20180808110258/https://static1.squarespace.com/static/5009f34d84aec201d50d1081/t/55942ee3e4b0f2c26b17c18f/1435774696888/?format=750w |url-status=dead |archive-date=2018-08-08 |publisher=Santa Barbara News Press |accessdate=8 August 2018}}</ref><ref>{{cite web |url=http://www.chessvariants.com/invention/sovereign-chess |last=Bates |first=Mark |title=Sovereign Chess |publisher=[[The Chess Variant Pages]] |date=25 March 2013 |access-date=19 April 2016 |archive-date=8 May 2016 |archive-url=https://web.archive.org/web/20160508180322/http://www.chessvariants.com/invention/sovereign-chess |url-status=live }}</ref>

==== Variant end-of-game rules ====
{{Chess diagram
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 |rd|nd|bd|qd|kd|bd|nd|rd
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 |pl|pl|pl|pl|pl|pl|pl|pl
 |rl|nl|bl|ql|kl|bl|nl|rl
 |'''Anti-king chess'''. The [[Fairy chess piece#Anti-King|anti-king]] is shown as an inverted king. White's anti-king starts on d6, while Black's anti-king starts on d3.
}}
* '''Anti-King chess''': Features an anti-king. The anti-king moves in the same way as a king. This piece is in check when not attacked. If a player's anti-king is in check and unable to move to a square attacked by the opponent, the player loses (checkmate). The anti-king cannot capture enemy pieces, but can capture friendly pieces. A king may not attack the opponent's anti-king. The anti-king may not check its own king. (That is, a position when a king and an anti-king are on adjacent squares is possible, does not mean any check and does not help the anti-king to avoid check if any other piece does not attack him.) Other rules are the same as in standard chess, including check and checkmate to the regular king. By Peter Aronson (2002).<ref>[http://www.chessvariants.org/diffobjective.dir/anti-king-chess.html Anti-King chess] {{Webarchive|url=https://web.archive.org/web/20060514082330/http://www.chessvariants.org/diffobjective.dir/anti-king-chess.html |date=2006-05-14 }} by Peter Aronson.</ref><ref>Two setups were suggested by the inventor initially, but only the second one (Anti-King II), which is very close to standard chess gained popularity.</ref>
* '''[[Apocalypse (chess variant)|Apocalypse]]''': On a 5×5 board, each side has two knights and five pawns, win by eliminating all enemy pawns. Prepared moves are executed simultaneously. By C. S. Elliott (1976).
* '''Colour Chess''': Played on a multicoloured board of six colours, with the order of turns taken as in '''Marseillais chess''' but with rules indicating which colour each piece may move to. The game is won by capturing the opponent's king (rather than checkmate) and kings may remain in check. Similar variants include '''Sequence Colour Chess''', and '''Swarm Colour Chess'''.<ref>{{Cite web|url=https://www.youtube.com/watch?v=5h03T_fwcHk| archive-url=https://ghostarchive.org/varchive/youtube/20211118/5h03T_fwcHk| archive-date=2021-11-18 | url-status=live|title=COLOUR CHESS - How to Play|date=September 1, 2017|via=YouTube}}{{cbignore}}</ref><ref>{{Cite web|url=https://www.dogearedgames.com/colourchess/|title=Colour Chess + Lure|access-date=2018-05-28|archive-date=2018-05-29|archive-url=https://web.archive.org/web/20180529130319/https://www.dogearedgames.com/colourchess/|url-status=live}}</ref>  By Tom Norfolk (2017).<ref>{{Cite web|url=https://boardgamegeek.com/boardgame/217977/colour-chess-lure|title=Colour Chess + Lure|website=BoardGameGeek|access-date=2018-05-28|archive-date=2018-05-28|archive-url=https://web.archive.org/web/20180528231130/https://boardgamegeek.com/boardgame/217977/colour-chess-lure|url-status=live}}</ref>
*'''{{vanchor|Duck Chess|text=Duck Chess}}''': In addition to the usual pieces, the two players have joint control of a small rubber duck which acts as a "blocker" (i.e. nothing can move onto or through it), and which must be moved to a new square after every turn. The goal is to successfully capture the opponent's king. A [[stalemate]]d player wins.<ref>{{Cite web |title=Duck Chess rules |url=https://duckchess.com/ |access-date=2022-05-19 |website=duckchess.com |archive-date=2022-05-19 |archive-url=https://web.archive.org/web/20220519003230/https://duckchess.com/ |url-status=live }}</ref>
* '''[[Extinction chess]]''': To win, a player must capture all of any one type of pieces of the opponent (for example, all the knights an opponent has, or all their pawns, etc.).
* '''[[Hexapawn]]''':  Played on a rectangular board of variable size with only pawns. The goal of each player is to advance one of their pawns to the opposite end of the board or to prevent the other player from moving.
{{Chess diagram 9x9
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 |[[Jeson Mor]] gameboard and starting setup
}}

* '''[[Jeson Mor|Jesön Mor]]''': Nine knights per side on a 9×9 board. The first to occupy square e5, and then leave it, wins the game. From Mongolia.
* {{Anchor|King of the Hill}}'''King of the Hill''': In addition to checkmate, a legal move that moves one's own king to one of the center squares (d4, d5, e4, e5), without moving illegally wins. This is analogous to [[Sannin shogi]]'s rule that allows a player to win by legally moving their king to the center.<ref>{{cite web|url=https://en.lichess.org/variant/kingOfTheHill|title=King of the Hill • Bring your King to the center to win the game. • lichess.org|website=en.lichess.org|access-date=2016-09-03|archive-date=2016-09-14|archive-url=https://web.archive.org/web/20160914014139/https://en.lichess.org/variant/kingOfTheHill|url-status=live}}</ref>
{{Chess diagram|clear=right
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 |pl|pl|pl|pl|pl|pl|pl|pl
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 |'''Knightmate''' starting position
}}
* {{Anchor|Knightmate}}'''Knightmate''' (or '''Mate The Knight'''): The goal is to checkmate the opponent's knight (initially on e-file). The kings on b- and g-files can be captured as other pieces. Pawns can promote to kings but not to knights. By Bruce Zimov (1972).<ref>[http://www.chessvariants.org/diffobjective.dir/knightmate.html Knightmate] {{Webarchive|url=https://web.archive.org/web/20060304103343/http://www.chessvariants.org/diffobjective.dir/knightmate.html |date=2006-03-04 }} by [[Hans Bodlaender]]</ref>
* '''[[Losing chess]]''' (or '''Antichess''', '''Giveaway chess''', '''Suicide chess''', '''Killer chess''', '''Take-all chess''', '''Take-me chess''', '''Reverse chess'''): Capturing moves are mandatory and the objective is to lose all one's pieces. There is no check; the king is captured like an ordinary piece.

{{Chess diagram|clear=right
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 |kd|rd|bd|nd|nl|bl|rl|kl
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 |'''[[Racing Kings]]''': first king to 8th rank wins
}}
* '''[[Racing Kings]]''': Players race kings to the 8th rank. Captures, but no checks or checkmate.{{sfnp|Pritchard|2000|p=41}}
* {{Anchor|Three-check chess}}'''[[Three-check chess]]''': Takes the "three strikes, you're out" rule from [[baseball]] and applies it to chess; standard rules of chess apply,<ref>{{cite web |title=Three-check • Check your opponent 3 times to win the game |url=https://lichess.org/variant/threeCheck |website=Lichess.Org |publisher=Lichness.org |access-date=30 July 2018 |archive-date=18 July 2018 |archive-url=https://web.archive.org/web/20180718144821/https://lichess.org/variant/threeCheck |url-status=live }}</ref> but a player can alternatively win by putting their opponent in check three times.{{sfnp |Pritchard |1994 |p=304}}<ref name=chess.com3check>{{cite web|url=https://www.chess.com/article/view/how-to-play-variants-on-chess-com|title=Chess Variants {{!}} 5 Amazing Examples|website=Chess.com|access-date=2018-07-19|archive-date=2018-07-19|archive-url=https://web.archive.org/web/20180719113800/https://www.chess.com/article/view/how-to-play-variants-on-chess-com|url-status=live}}</ref><ref>{{cite web |title=Teaching Chess the Easy and Fun Way with Mini-Games - UIL |url=http://www.uiltexas.org/files/capitalconference/Randolph-TeachingChesstheEasyFunWaywithMiniGames.pdf |archive-url=https://web.archive.org/web/20140327090603/http://www.uiltexas.org/files/capitalconference/Randolph-TeachingChesstheEasyFunWaywithMiniGames.pdf |archive-date=2014-03-27 |url-status=live |website=Teaching Chess the Easy and Fun Way with Mini-Games |access-date=30 July 2018}}</ref> In ''The Encyclopedia of Chess Variants'', [[David Pritchard (chess player)|David Pritchard]] notes it being of probable Soviet origin, and that [[Anatoly Karpov]] was an "invincible" player in his youth.{{sfnp |Pritchard |1994 |p=304}}{{sfnp |Pritchard |2007 |p=83}}

=== Non-rectangular board ===
[[File:Rundskak foto.jpg|thumb|upright=1.2|[[Circular chess]] ]]
[[File:Infinite chess.png|thumb|upright=1.2|'''[[Infinite chess]]'''. One example with pieces in their standard positions.<ref name="PBS">[https://www.youtube.com/watch?v=PN-I6u-AxMg "Infinite Chess, PBS Infinite Series"] {{Webarchive|url=https://web.archive.org/web/20170407211614/https://www.youtube.com/watch?v=PN-I6u-AxMg |date=2017-04-07 }} PBS Infinite Series, with academic citations including "''Transfinite game values in infinite chess''" (2013)</ref>]]
[[File:Masonic Chess gameboard and init config - alt framing.PNG|thumb|upright=1.2|'''[[Masonic Chess]]''' by George Dekle Sr.]]
[[File:Rhombic Chess gameboard and starting position.png|thumb|upright=1.2|'''[[Rhombic Chess]]''' by Tony Paletta]]

In this category, the movement of pieces can be modified in concurrence with the geometry of the board.<ref name=":1">{{cite magazine |last1=Jelliss |first1=G. P. |title=Reshaping the Chessboard |publisher=[[British Chess Variants Society]] |magazine=[[Variant Chess]] |date=Autumn 1997 |volume=3 |issue=25 |pages=92–93 |issn=0958-8248 }}</ref>

==== Hexagonal spaces ====
{{main|Hexagonal Chess}}
* '''Baskerville's hexagonal chess''': Earliest attempt at a strict hexagonal analog to chess. 83 cell hex board with four corners. Same as '''Gliński's Hexagonal Chess''', but no special pawn moves or hex diagonal king moves. Opposing bishops occupy differently colored spaces, thus preventing them from attacking each other. By H. D. Baskerville (1929).
* '''[[Brusky's hexagonal chess]]''': Chess on an irregular board of 84 hex cells. Same as '''Gliński's Hexagonal Chess''', but with ten pawns instead of nine, linear startup, two forward move directions for pawns, pawns capture forward diagonally, and castling. By Yakov Brusky (1966).
* '''[[Hexagonal chess#De Vasa's hexagonal chess|De Vasa's hexagonal chess]]''': Chess on a rhombus-shaped board of 81 hex cells. Same as '''Gliński's Hexagonal Chess''', but linear startup, two forward move directions for pawns, pawns capture forward diagonally to the side, and castling. Invented by Helge E. de Vasa (1953).
* '''[[Gliński's hexagonal chess]]''': The most popular version of chess for the hex board. Includes three bishops, nine pawns, 91 hex cells. Invented by Władysław Gliński (1936).
* '''[[McCooey's hexagonal chess]]''': Chess on the same hexagonal board as Gliński's Hexagonal Chess, but using a different starting array, seven pawns instead of nine, and pawns capture forward diagonally. By Richard Honeycutt and David McCooey (1978&ndash;1979).
* '''[[Hexagonal chess#Starchess|Polgar Superstar Chess]]''': Hexagonal variant played on a special star-shaped board. Invented by [[László Polgár]] (2002).<ref>''[http://www.mayhematics.com/v/vol8/vc61.pdf Variant Chess] {{Webarchive|url=https://web.archive.org/web/20110714054644/http://www.mayhematics.com/v/vol8/vc61.pdf |date=2011-07-14 }}'', Vol 8, Issue 61</ref><ref>{{Cite web|url=http://polgarstarchess.blogspot.com/search/label/Patent|title=Polgar Superstar Chess Patent|date=March 6, 2009|access-date=February 24, 2011|archive-date=November 6, 2018|archive-url=https://web.archive.org/web/20181106235135/http://polgarstarchess.blogspot.com/search/label/Patent|url-status=live}}</ref>
* '''[[Shafran's hexagonal chess]]''': Chess on an irregular hex board of 70 cells. Same as '''Gliński's Hexagonal Chess''', but differs by starting position, pawn first-move options, pawns capturing forward diagonally, and castling. Invented by Grigorevich Shafran (1939).
* '''Strozewski's hexagonal chess''': Chess on a square-shaped board of 81 hex cells. King and Knight move as if cells were squares. Invented by Casimir S. Strozewski (1976).
* '''{{vanchor|Troy}}''': A variant inspired by the [[Trojan War]] played on a 91-cell hexagonal board. Pieces are named after characters from the myth.{{sfnp|Pritchard|2007|p=206|ps=}}

==== Triangular spaces ====
* '''[[Tri-Chess (2-player)|Tri-Chess]]''': A variation of Triangular Chess. The rook and bishop are increased to six directions; the queen, to twelve. By George Dekle Sr.
* '''[[Triangular Chess]]''': Board comprises 96 triangles. The rook and bishop have three directions; the queen, six. Three extra pawns and a unicorn. By George Dekle Sr.

==== Other 2D layouts ====
* '''[[Balbo's Game]]''': A novel-shaped board with 70 squares. Full armies for each player, minus one pawn. No castling. By G. Balbo (1974).
* '''[[Chessence]]''': Nine pieces per player move according to their relative positions to each other on a 6×9 board with missing squares and kings immobile in the corners. By Jim Winslow (1989).
* '''[[Circular chess]]''': Played on a circular board consisting of four rings, each of sixteen squares.
* '''[[Cross chess]]''': Cross-shaped cells, board geometry like hex chess but moves akin to normal chess (e.g. bishops have four directions, not six; queens eight, not twelve). Extra rook, knight, and pawn per side. By George Dekle Sr.
* '''[[Cylinder chess]]''': Played on a cylinder board with a- and h-files "connected". Thus a player can use them as if the a-file were next to the h-file (and vice versa).
* '''[[Infinite chess]]''': Numerous players and mathematicians have conceived of chess variations played on an unbounded chessboard.<ref name="PBS"/> In one example, when using "Converse's rules," the pieces and their relative starting positions are unchanged—only the board is infinitely large.<ref name="IC">[http://www.chessvariants.com/boardrules.dir/infinite.html Infinite Chess] {{Webarchive|url=https://web.archive.org/web/20170402082426/http://www.chessvariants.com/boardrules.dir/infinite.html |date=2017-04-02 }} at ''The Chess Variant Pages''. An infinite chess scheme represented using ASCII characters.</ref>
* '''[[Masonic Chess]]''': Every other board rank is indented. Same as chess, with moves adapted to the new brickwork-like board. By George Dekle Sr.
* '''[[Omega chess]]''': On a 10×10 board with four extra squares, one per corner. Includes the champion and wizard fairy pieces. Both are leapers, with different ways of leaping.
* '''[[Rhombic Chess]]''': Uses a hex-shaped board comprising 72 rhombus cells. Normal set of chess pieces move ''edgewise'' or ''pointwise''. Checkmate objective as usual. By Tony Paletta (1980).
* '''[[Rollerball (chess variant)|Rollerball]]''': Inspired by the sci-fi film of the same name, pieces move clockwise around a Roller Derby-like track. By Jean-Louis Cazaux (1998).
* '''[[Spherical chess]]''' [multivariant]: A family of variants played on a chessboard wrapped around a sphere. The a- and h-files are adjacent. The poles are circular or octagonal and may or may not be occupied according to the variant. There are no board edges, so kings always have eight adjacent squares. Trans-polar diagonal moves mostly differentiate between variants.{{sfnp|Pritchard|2007|p=223|ps=}}{{sfnp|Pritchard|1994|pp=285–86|ps=}}
*'''Thrones Chess''':{{citation needed|date=July 2023|reason=Current citation is a dead link.}} Uses a board that combines a circular component and a square component, which allows long-range pieces to attack from three sides. The board is divided into two castles and a battlefield. A piece cannot cross more than two castle walls in the same move, and a king in check may not leave a castle except to capture the piece giving check. Knights have additional non-capturing moves. By Richard Van de Venter (1999). [[File:Thrones Chess initial setup.png|alt=|thumb|Thrones Chess, initial setup with the classic chess pieces. Free squares may be filled by additional classic or fairy chess pieces.]]
* '''Zonal chess''': Board has triangular wings or "zones" on either side of the main 8×8 board. Queens, bishops, and rooks that start from one of the squares in either zone may change direction and keep going on the same move. A queen, for example, could zig around an obstruction and attack a piece in the opposite zone. The power to change direction only applies when a piece's move starts from a zonal area. It is possible (using the queen and rook) to cross the board from one zone to another, but any piece entering a zone cannot make use of the extended move.<ref>[http://www.chessvariants.org/shape.dir/zonal/zonal.html "Zonal Chess"] {{Webarchive|url=https://web.archive.org/web/20060306034211/http://www.chessvariants.org/shape.dir/zonal/zonal.html |date=2006-03-06 }} by Larry Smith, ''[[The Chess Variant Pages]]''</ref>

==== Higher dimensional boards ====
{{3D_chess_diagram
|tight
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|pd|pd|pd|pd|pd|pd|pd|pd  
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|rd|nd|bd|qd|kd|bd|nd|rd
|pd|pd|pd|pd|pd|pd|pd|pd  
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|pl|pl|pl|pl|pl|pl|pl|pl
|rl|nl|bl|ql|kl|bl|nl|rl
||[[Parallel Worlds Chess]], a 3D variant
}}
{{Main|Three-dimensional chess}}
A number of variants have been developed where the playing area is in three [[dimension]]s or more. In most cases an extra spatial dimension is represented by multiple boards being laid next to each other. Some extra-dimensional variants attempt to reflect the 3D nature of modern warfare (e.g. ''[[Raumschach]]'', designed to reflect [[Aerial warfare|aerial]] and [[submarine warfare]]), while others incorporate fantasy or science fiction ideas such as [[Multiverse|parallel worlds]] and [[time travel]].<ref>{{Cite web|title=5D Chess With Multiverse Time Travel Press Kit|url=https://www.5dchesswithmultiversetimetravel.com/presskit.html|access-date=2020-07-27|website=5dchesswithmultiversetimetravel.com|archive-date=2020-07-27|archive-url=https://web.archive.org/web/20200727222326/https://www.5dchesswithmultiversetimetravel.com/presskit.html|url-status=live}}</ref><ref>Prichard (2007) p. 226</ref> An example of the latter is the variant introduced by the 2020 computer game ''[[5D Chess With Multiverse Time Travel|5D Chess with Multiverse Time Travel]]'', which uses a varying number of boards all being played in parallel.
{{clear left}}

*'''''[[5D Chess with Multiverse Time Travel]]''''': Players can move their pieces through time and between timelines, interacting with the board as it existed earlier in the game, creating alternate timelines which pieces can be moved between. The game is won if at least one king from any time and timeline is in checkmate.<ref>{{Cite web|last=Livingston|first=Christopher|date=2020-07-27|title=If regular chess isn't hard enough for you, try 5D Chess With Multiverse Time Travel|url=https://www.pcgamer.com/if-regular-chess-isnt-hard-enough-for-you-try-5d-chess-with-multiverse-time-travel/|access-date=2021-06-09|website=PC Gamer|archive-date=2020-08-04|archive-url=https://web.archive.org/web/20200804032348/https://www.pcgamer.com/if-regular-chess-isnt-hard-enough-for-you-try-5d-chess-with-multiverse-time-travel/|url-status=live}}</ref>
* '''Flying chess''': Played on a board of 8×8×2, giving a total of 128 cells. Only certain pieces can move to and from the additional level.{{sfnp|Pritchard|2007|p=226|ps=}}
* '''[[Parallel Worlds Chess]]''': A 3D variant using three boards, each player commands two armies, capturing either enemy king wins. The middle board is a sort of "twilight zone" obeying its own rules. By R. Wayne Schmittberger (1980s).

==== Multiple boards ====
* '''[[Alice Chess]]''': Played with two boards: a piece moved on one board passes "through the looking glass" onto the other board. By [[V. R. Parton]] (1953).
* '''[[Chesquerque]]''': Played on four [[Alquerque]] boards combined. Includes an extra pawn and [[Princess (chess)|archbishop]] per side. By George Dekle Sr.
* '''Regimental Chess''': This variant is played on 1-6 adjacent 12×16 boards, with one white and black division for each board signified by accent colours. Each division starts with 14 infantrymen, similar to pawns but only moving one space at a time straight or diagonally forward until promoted to move one space in any direction, four bishops, four knights, four rooks, two queens and one king, and players may place their pieces into their own formation before the game starts. When a division's king is captured, all other pieces from that division are removed from the battlefield. Pieces can move together as formations, which are connected by any compatible pieces that are adjacent or mutually supportive with one another, and capture pieces by broadsiding with walls of pieces or piercing inferior ranks with superior firepower. Pieces are mutually supportive if they are identical and are within reach of their move style; for example, two bishops are mutually supportive if they are on an adjacent diagonal path unobstructed by other pieces.<ref>[https://store.steampowered.com/app/362400/Regimental_Chess/ Regimental Chess on Steam] {{Webarchive|url=https://web.archive.org/web/20220410002434/https://store.steampowered.com/app/362400/Regimental_Chess/ |date=2022-04-10 }}, [https://youtube.com/user/regimentalchess YouTube channel for Regimental Chess] {{Webarchive|url=https://web.archive.org/web/20220410002434/https://www.youtube.com/user/regimentalchess |date=2022-04-10 }}</ref>

=== Variant player count ===
[[File:Bughouse game.jpg|right|thumb|275px|'''[[Bughouse chess]]''', the game in progress]]
* '''[[Bosworth (game)|Bosworth]]''': A four-player variant played on 6×6 board. It uses a special card system with the pieces for spawning.
* '''[[Bughouse chess]]''' (or '''Exchange chess''', '''Siamese chess''', '''Swap chess''', '''Tandem chess''', '''Transfer Chess'''): Two teams of two players face each other on two boards. Allies use opposite colours and give captured pieces to their partner. The two-player version of the game, played with only one board, is [[Crazyhouse]].
* '''[[Business chess]]''' [multivariant]: Played with two teams using normal chess playing rules but allowing up to five variations of the game. The team may discuss and play alternative moves freely.
* '''[[Djambi]]''': Can be played by four players on a 9×9 board and four sets of special pieces. Pieces can capture or move those of an adversary. Captured pieces are not removed from the board, but turned upside down. There are variants for three or five players (''Pentachiavel''). (1975)
* '''[[Duchess (chess variant)|Duchess]]''': Notable for its wide variety of player counts; supports 2, 3, 4, or 6 players in a free-for-all, as well as 2v2, 2v2v2, or 3v3 team play. The board consists of one 4×5 "petal" for each player. These surround a core hexagonal board, which itself has two rings of squares around a central hexagonal "vortex" space. Three Fairy Chess pieces are used, the titular [[Princess (chess)|Duchess]] (princess), the [[Empress (chess)|Fortress]] (empress), and the Wizard, capable of teleporting friendly pieces.
* '''[[Enochian chess]]''': A four-player variant with magical symbolism, associated with the [[Hermetic Order of the Golden Dawn]].
* '''[[Forchess]]''': A four-player variant using the standard board and two sets of standard pieces.
* '''[[Fortress chess]]''': A four-player variant played in Russia in 18th and 19th centuries.
* '''[[Four Fronts]]''': A four-player variant created in 2012 by a Uruguayan professor named Gabriel Baldi Lemonnier.<ref>{{cite web|url= http://www.elobservador.com.uy/noticia/255616/se-necesitan-cuatro-para-jugar-ajedrez/|author=Luis Roux |title= Se necesitan cuatro para jugar ajedrez|work= El Observador|date= 20 July 2013|accessdate= 20 July 2013|trans-title=It takes four to play chess|language= es|location= Uruguay |archive-url= https://web.archive.org/web/20130726232119/http://www.elobservador.com.uy/noticia/255616/se-necesitan-cuatro-para-jugar-ajedrez/|archive-date= 26 July 2013|url-status= dead}}</ref>
* '''[[Four-player chess]]''' (or  '''Four-handed''', '''4-Player'''): Can be played by four people and uses a special board and two sets of differently coloured pieces. Two modes includes: Teams or Free For All. 
* '''[[Hand and brain]]''': Teams of two play against each other; in each team, one player is the "brain" and calls out a piece type, while the "hand" player chooses which piece of that type to move and where to move it.
* '''[[Quatrochess]]''': A four-player variant, in addition to the standard chess army, each side controls a chancellor, archbishop, mann, wazir, fers, two camels, and two giraffes. By George Dekle Sr.
* '''[[Three-Man Chess]]''': Three chessboard halves fused into one, first to checkmate wins. By George Dekle Sr.
* '''[[Tri-Chess]]''': For three players; 150 triangular cells; [[Empress (chess)|chancellor]] (empress) and [[Princess (chess)|cardinal]] (princess) replacing queen. By George Dekle Sr.

=== Variants with hidden information or use of chance ===
In contrast to standard chess, which is a game of [[complete information]], in these variants, the players do not have [[perfect information]] about the state of the board, or there is an element of chance in how the game is played after the initial setup of pieces.
*'''[[Beirut Chess]]''': Each player secretly equips one of their pieces with a “bomb” that can be detonated at any time, wiping out all pieces on adjacent squares. Win by  checkmating the opponent, or blowing up their king. By Jim Winslow (1992).
* '''ChessHeads''': Played with cards that change the game rules.<ref>[http://www.chessmate.com/ChessHeads.html ChessHeads] {{Webarchive|url=https://web.archive.org/web/20090328231508/http://www.chessmate.com/ChessHeads.html |date=2009-03-28 }} chessmate.com</ref><ref>[http://www.boardgamegeek.com/boardgame/12932 ChessHeads] {{Webarchive|url=https://web.archive.org/web/20091121134408/http://www.boardgamegeek.com/boardgame/12932 |date=2009-11-21 }} BoardGameGeek</ref>
* '''Choker:''' A combination of chess and [[poker]], with players betting on cards made up from pieces of a standard chess set.<ref>{{Cite web |title=CHOKER Launch New Game Combining Chess and Poker |url=https://www.pokertube.com/article/choker-launch-new-game-combining-chess-and-poker |access-date=2022-03-15 |website=PokerTube |archive-date=2023-03-14 |archive-url=https://web.archive.org/web/20230314210117/https://www.pokertube.com/article/choker-launch-new-game-combining-chess-and-poker |url-status=live }}</ref>
* '''[[Dark chess]]''' (or '''Fog of War chess'''): The player sees only squares of the board that are attacked by their pieces.<ref>{{cite web |title=What is Fog of War chess? |url=https://support.chess.com/article/1668-what-is-fog-of-war-chess |accessdate=April 8, 2021 |website=[[Chess.com]] |archive-date=April 13, 2021 |archive-url=https://web.archive.org/web/20210413025755/https://support.chess.com/article/1668-what-is-fog-of-war-chess |url-status=live }}</ref>
* '''[[Dice chess]]''' [multivariant]: The pieces a player is able to move are determined by rolling a pair of dice.{{sfnp|Pritchard|2007|pp=277-280}}
* '''Fantasy Chess''': Chess with wargaming added. Players fight for squares (which can be co-occupied) using dice. Can be expanded to four players; piece capability can improve each game.<ref>{{Cite web|url=https://www.shadowhex.com/|title=home page for Fantasy Chess|website=shadowhex.com|access-date=2019-06-22|archive-date=2019-07-30|archive-url=https://web.archive.org/web/20190730032025/https://www.shadowhex.com/|url-status=live}}</ref>
* '''[[Knightmare Chess]]''': Played with cards that change the game rules.
* '''[[Kriegspiel (chess)|Kriegspiel]]''': Neither player knows where the opponent's pieces are but can deduce them with information from a referee.
* '''No Stress Chess''': Marketed for teaching beginners, the piece(s) a player is able to move are determined by drawing from a deck of cards, with each card providing the rules for how the piece may move. Castling and ''[[en passant]]'' are disallowed.<ref>{{Cite web|url=https://boardgamegeek.com/boardgame/19918/no-stress-chess|title=No Stress Chess|website=BoardGameGeek|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050215/https://boardgamegeek.com/boardgame/19918/no-stress-chess|url-status=live}}</ref>
* '''Panic Chess''': Player selects a piece to move, but the target square is randomized from all possible options. Captures are prioritized over non-capture moves. King, if no capture is possible, prioritizes a square not attacked by the opponent. Play ends with capture of king.<ref>{{Cite web|url=https://oreszczuk.pl/panicchess/|title=home page for Panic Chess|website=oreszczuk.pl|access-date=2022-11-01|archive-date=2022-11-01|archive-url=https://web.archive.org/web/20221101205759/https://oreszczuk.pl/panicchess/|url-status=live}}</ref>
* '''Playing cards on a chessboard''': A card game allowing open play on a board with rectangular sectors, just as in chess or [[Draughts|checkers]], but with the application of playing cards.<ref>{{Cite web|url=http://www.cardgameopen.64g.ru/en.htm|title=Playing card games on a chess board|access-date=2011-03-28|archive-date=2011-08-07|archive-url=https://web.archive.org/web/20110807040740/http://cardgameopen.64g.ru/en.htm|url-status=live}}</ref>
* '''Pokémon Chess''': Each player assigns a type from Pokémon to each of their pieces before the game starts. A capture on a piece depends on the type of the attacking piece and defending piece: If the attacking piece's type is super-effective towards the defending piece, the attacking piece gets to move again. If the attack is not very effective, both pieces will die, and if the defender is immune, the move is skipped. Additionally, on every capture, there is a chance of hitting a critical hit or missing, which makes the attacker go again or have their move skipped respectively. A player wins when they capture their opponent's king; there is no check.<ref>{{Cite web|url=https://pokemonchess.com/|title=Pokemon Chess|access-date=2024-01-11|archive-date=2024-01-11|archive-url=https://web.archive.org/web/20240111222334/https://pokemonchess.com/|url-status=live}}</ref>
* '''Quantum Chess''': Instead of a making a standard move, a player can make a "quantum move", which splits the piece being moved into a "superposition" of two locations, each with their own "probability". (Pawns cannot make quantum moves.) A succession of quantum moves can result in a piece being split into several superpositions. When that piece interacts with another piece, a measurement occurs, which causes the superpositions formed by the most recent quantum move in the history of that piece to be consolidated into a single location. The location of that consolidation depends randomly on the probabilities of the different superpositions. Playing the game by hand would require complex mathematical computations and a means of random number generation. There is a computer implementation available on the [[Steam (service)|computer game platform Steam]].<ref>{{Cite web|url=https://news.usc.edu/91856/the-next-generation-of-chess-is-here-and-it-involves-quantum-physics/|title=The next generation of chess is here, and it involves quantum mechanics|date=11 February 2016|access-date=24 June 2023|archive-date=24 June 2023|archive-url=https://web.archive.org/web/20230624230757/https://news.usc.edu/91856/the-next-generation-of-chess-is-here-and-it-involves-quantum-physics/|url-status=live}}</ref>
* '''Synchronous Chess''': Players try to outguess each other, moving simultaneously after privately recording intended moves and anticipated results. Incompatible moves, for instance to the same square with no anticipated capture, are replayed. Alternatively, two pieces moving to the same square are both captured, unless one is the king, in which case it captures the other. Play ends with capture of king.{{sfnp|Pritchard|2007|p=100}}
* '''Viennese Chess''': A barrier or screen between the two halves of the chessboard, two players then place their pieces on their half of the board. The barrier is then lifted and the game is then played as in standard chess.<ref>{{Cite web|url=https://www.chessvariants.com/diffsetup.dir/viennese.html|title=Viennese Chess|website=chessvariants.com|access-date=2019-06-22|archive-date=2019-06-22|archive-url=https://web.archive.org/web/20190622050213/https://www.chessvariants.com/diffsetup.dir/viennese.html|url-status=live}}</ref>

== Games inspired by chess ==
These variants are very different from chess and may be classified as [[Abstract strategy game|abstract strategy]] [[board game]]s instead of chess variants.
* '''[[Arimaa]]''': A game designed in 2002 to be easy for people to understand but difficult for computers to play well. The [[Arimaa#Arimaa Challenge|Arimaa Challenge]] was a cash prize offered for developing a program able to defeat the top human Arimaa players; this was claimed in 2015.
*[[Hive (game)|'''Hive''']]: a bug-themed [[abstract strategy]] game designed by John Yianni and published in 2001 by Gen42 Games. The object of ''Hive'' is to capture the opponent's queen bee by completely surrounding it, while avoiding the capture of one's own queen.
* '''[[Martian chess]]''': Played with [[Icehouse pieces]].
* '''[[Navia Dratp]]''': A cross between [[shogi]] and [[miniature wargaming]].
* '''[[Penultima (game)|Penultima]]''': An inductive variant where the players must deduce hidden rules invented by "Spectators".
* '''[[Superchess]]''': 4-player chess game published in 1992 by Green Island game
* '''[[The Duke (board game)|The Duke]]''': An abstract strategy game where the board, pieces, and gameplay mechanics have some strong parallels with chess.

==Chess-related historical and regional games==
Some of these games have developed independently while others are ancestors or relatives of modern chess.<ref>{{cite book |last=Murray |first=H. J. R. |author-link=H. J. R. Murray | title=A History of Chess
|publisher=Benjamin Press (originally published by Oxford University Press)| year=1913 | isbn=978-0-936317-01-4|title-link=A History of Chess }}</ref>{{page needed|date=December 2024}}<!--Applies to the claim that they have developed independently from chess. In any case, the article 'chess variant' states that a chess variant is a game related to, derived from, or inspired by chess. So, by definition, if the are not ancestors or relatives of modern chess, they are not 'chess variants' and are irrelevant to this page.--> The popularity of these variants may be limited to their respective places of origin (as is largely the case for shogi), or worldwide (as is the case for xiangqi). The games have their own institutions and traditions.

===Historical===
[[File:Chess Set MET DP170393.jpg|thumb|right|'''[[Shatranj]]''' set, 12th century]]
{{Chess diagram svg
 |tright|check=no
 |
 |sy|py|  |  |kb|eb|nb|sb
 |ny|py|  |  |pb|pb|pb|pb
 |ey|py|  |  |  |  |  |
 |ky|py|  |  |  |  |  |
 |  |  |  |  |  |  |pr|kr
 |  |  |  |  |  |  |pr|er
 |pg|pg|pg|pg|  |  |pr|nr
 |sg|ng|eg|kg|  |  |pr|sr
 |'''[[Chaturaji]]'''
}}
* '''[[Chaturaji]]''': Four-handed version of [[chaturanga]], played with dice.
* '''[[Chaturanga]]''': An ancient East Indian game, presumed to be the [[origins of chess|common ancestor of chess]] and other national chess-related games.
* '''[[Courier chess]]''': Played in Europe from 13th to 19th century. Probably was one step in evolving modern chess out of [[shatranj]].
* '''[[Grant Acedrex]]''': Medieval Spanish variant from 13th century.
* '''[[Shatranj]]''': An ancient Persian game, derived from [[chaturanga]].
* '''[[Short assize]]''': Played in England and Paris in the second half of the 12th century.
* '''[[Tamerlane chess]]''': A significantly expanded variation of [[shatranj]].

=== Regional ===
{{multiple image |total_width = 680 
 |align=right
 |image1=Shogi init config.png
 |width1=991 |height1 = 1117
 |caption1='''[[Shogi]]'''
 |image2=Xiangqi Board.svg
 |width2=600 |height2 = 660
 |caption2='''[[Xiangqi]]'''
 |image3=Sittuyin starting position No. 8.PNG
 |width3=1178 |height3 = 1178
 |caption3='''[[Sittuyin]]''', players elect their own starting setups behind the pawns
}}
* '''[[Banqi]]''' (or '''Chinese Half chess''') (China)
* '''Chandraki''' (Tibet)
* '''[[Game of the Three Kingdoms]]''' (China)
* '''[[Shatar#Hiashatar|Hiashatar]]''' (Mongolia)
*'''[[Indian chess]]''' (India)
* '''[[Janggi]]''' (Korea; see also [[janggi variant]]s)
* '''[[Jungle (board game)|Jungle]]''' (or '''Dou Shou Qi''', '''The Jungle Game''', '''Jungle Chess''', '''Animals Chess''', '''Oriental Chess''', '''Children's Chess''') (China)
* '''Main chator''' (Malaysia, Indonesia, Philippines)
* '''[[Makruk]]''' (Thailand and Cambodia)
* '''[[Ouk Chatrang]]''' (Cambodia)
* '''[[Rek Chess]]''' (Cambodia)
* '''Samantsy''' (Madagascar)
* '''[[Senterej]]''' (Ethiopia and Eritrea)
* '''[[Shatar]]''' (Mongolia)
* '''[[Shogi]]''' (Japan; see also [[shogi variant]]s, especially [[chu shogi]])
* '''[[Sittuyin]]''' (Burma)
* '''[[Xiangqi]]''' (China; see also [[xiangqi variant]]s)

==See also==
{{Div col}}
* [[Advanced chess|Advanced chess, Centaur chess or Cyborg chess]]
* [[Blindfold chess]]
* [[Correspondence chess]]
* [[Fast chess|Blitz chess]]
* [[Chess as mental training]]
* [[Chess boxing]]
* [[The Chess Variant Pages]]
* [[Fairy chess]]
* [[Fairy chess piece]]s
* [[Infinite chess]] (a class of chess games)
* [[Janggi variant]]
* [[List of abstract strategy games]]
* [[Outline of chess#Chess variants|Outline of chess: Chess variants]]
* [[Shogi variant]]
* [[Xiangqi variant]]
{{div col end}}

== Notes ==
{{notelist}}

==References==
{{reflist}}

'''Bibliography'''
* {{Cite book|title=A World of Chess, Its Development and Variations through Centuries and Civilizations |last1=Cazaux|first1=Jean-Louis|publisher=McFarland|year=2017|isbn=978-0-7864-9427-9|last2=Knowlton|first2=Rick}}
*{{cite book
 |last=Gollon
 |first=John
 |title=Chess Variations • Ancient, Regional, and Modern
 |publisher=[[Tuttle Publishing|Charles E. Tuttle Company Inc]] 
 |year=1968
 |lccn=06811975}}
*{{cite book
 |last=Murray
 |first=H. J. R.
 |author-link=H. J. R. Murray
 |title=A History of Chess
 |edition=Reissued
 |publisher=[[Oxford University Press]]
 |year=1913
 |isbn=978-0-19-827403-2}}
*{{cite book
 |last=Pritchard 
 |first=D. B. 
 |author-link=David Pritchard (chess player)
 |title=The Encyclopedia of Chess Variants
 |publisher=Games & Puzzles Publications
 |year=1994
 |isbn=978-0-9524142-0-9
 }}
*{{cite book
 |last=Pritchard 
 |first=D. B. 
 |author-link=David Pritchard (chess player)
 |title=Popular Chess Variants
 |publisher=Batsford Chess Books
 |year=2000
 |isbn=978-0-7134-8578-3
 }}
*{{cite book
 |last=Pritchard 
 |first=D. B. 
 |author-link=David Pritchard (chess player)
 |editor-last=Beasley
 |editor-first=John
 |title=The Classified Encyclopedia of Chess Variants
 |publisher=John Beasley 
 |url=https://www.jsbeasley.co.uk/encyc/encyc.pdf |archive-url=https://web.archive.org/web/20180813210317/https://www.jsbeasley.co.uk/encyc/encyc.pdf |archive-date=2018-08-13 |url-status=live
 |year=2007
 |isbn=978-0-9555168-0-1
 }}

==Further reading==
*{{cite book
 |last=Murali
 |first=A V
 |title=Chess Variants & Games for Intellectual Development and Amusement
 |publisher=Leadstart Publishing Pvt. Ltd.
 |year=2011
 |isbn=978-93-8111-574-9}}
*{{cite book
 |last=Schmittberger
 |first=R. Wayne
 |title=New Rules for Classic Games
 |publisher=John Wiley & Sons Inc
 |year=1992
 |isbn=978-0471536215
 |url=https://archive.org/details/newrulesforclass00rway
 }}

'''Shogi'''
*{{cite book
 |last=Leggett
 |first=Trevor
 |title=Japanese Chess: The Game of Shogi
 |publisher=Tuttle Publishing
 |year=2009
 |isbn=978-4-8053-1036-6}}
*{{cite book
 |last=Teruichi
 |first=Aono
 |title=Better Moves for Better Shogi
 |publisher=Ishi Press
 |year=2009
 |isbn=978-4-87187-999-6}}

'''Xiangqi'''
*{{cite book
 |last=Liu
 |first=Alex
 |title=How To: Chinese Chess for Beginner
 |publisher=Foreign Languages Press
 |year=2005
 |isbn=978-7-119-04208-4}}
*{{cite book
 |last=Sloan
 |first=Sam
 |title=Chinese Chess for Beginners
 |publisher=Ishi Press
 |year=2006
 |isbn=978-0-923891-11-4}}

'''Others'''
*{{Cite book|title=Traité pratique de Métamachie|last=Cazaux|first=Jean-Louis|publisher=Pionissimo|year=2012|isbn=978-2-9541313-0-6}}
*{{Cite book|title=Thai Chess and Cambodian Chess, Makruk and Ouk Chatrang|last=Gifford|first=Gary|publisher=Lulu Publishing|year=2011|isbn=978-1-4357-8470-3}}
*{{Cite book|title=Play Hive like a Champion|last=Ingersoll|first=Randy|year=2013|isbn=978-1-4944-7664-9|location=Port Orange, FL}}
*{{cite book
 |last=Juhnke
 |first=Fritz 
 |title=Beginning Arimaa: Chess Reborn Beyond Computer Comprehension
 |publisher=Flying Camel Publications
 |year=2009
 |isbn=978-0-9824274-0-8}}
*{{cite book
 |last=Schmittberger
 |first=R. Wayne
 |title=Thai Chess & Cambodian Chess (Makruk & Ouk Chatrang)
 |publisher=Wiley
 |year=1992
 }}
*{{cite book
 |editor-last=von Zimmerman
 |editor-first=Georg
 |title=Bughouse Chess
 |publisher=Books on Demand GmbH
 |year=2006
 |isbn=978-3-8334-6811-7}}
*{{cite book
 |last=Zorzos
 |first=Gregory 
 |title=Atherma ZATRIKION (Chess): Ancient Greek board game Chess
 |publisher=CreateSpace
 |year=2009
 |isbn=978-1-4421-2636-7}}

==External links==
{{commons category|Chess variants}}
* [http://www.mayhematics.com/s/s.htm British Chess Variants Society] (archive)
* [http://www.tradgames.org.uk/games/Chess.htm The Chess Family - History and Useful Information]
* [http://www.pathguy.com/chess/ChessVar.htm Chess Variant Applets] Java Applets, which allow playing many chess variants against computer
* [http://www.chessvariants.org ''The Chess Variant Pages'']
* [http://chessvariants.wikidot.com/ The Chess Variants wiki]
* [https://www.chess.com/forum/view/chess960-chess-variants/comparison-of-material-power-in-variant-chess-games Comparison of Material Power in Variant Chess Games]
* [http://history.chess.free.fr/ Variety and history of Chess in ancient world]
* [https://lookintochess.com/chess-variants/ Chess variants with sample games and analyses]
{{chess}}
{{Chess variants|state=expanded}}

{{DEFAULTSORT:Chess variants}}
[[Category:Chess variants| ]]
[[Category:Lists of game variants|Chess]]