Editing List of chess variants (section)

==== 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
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|''[[Chad (chess variant)|Chad]]'' by Christian Freeling
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* '''[[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
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 |rd| | |qd| |rd|kd|
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 |'''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>