====== Chess ======

No abstract games site is complete without **Chess**. It is normally played with White and Black armies on an 8×8 board, with White moving first. Chess is characterised by powerful long-ranging pieces and several special rules, including castling, promotion, and en passant. The objective is to checkmate the opponent's King, while stalemate results in a draw.

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Chess is extremely well taught and documented elsewhere, so we will not reproduce the complete rules here. If you are unfamiliar with it, check out some sites here:

  * https://lichess.org/learn
  * https://www.chess.com/learn-how-to-play-chess
  * Full technical rules: https://rcc.fide.com/fide-laws-of-chess_fulltexthtml/

If you're interested in Chess, you're in luck because it is perhaps one of the biggest abstract games in history, and you can always find live players to match up with at any time of the day. Chess.com and Lichess above are some of the best places to start, but there are probably hundreds of other places to play online.

====== Variants ======

  * https://www.chessvariants.com/
  * https://jsbeasley.co.uk/
  * https://www.solitairelaboratory.com/chessvariants/WGR10.html
  * https://www.di.fc.ul.pt/~jpn/cv/mutators.htm

There is an abundance of Chess variants. Many can be understood in terms of **mutators**: rules that change one particular aspect of ordinary Chess, such as the initial setup, movement, captures, turn structure, or winning condition, while leaving most of the game intact.

In principle, many of these mutators can be combined. Rather than implementing every possible combination, I generally include only established forms of a variant. Most of the time, it is also more interesting to experience the effect of each mutator on its own. More combinations may be considered in the future when there is evidence of an established culture around them.

The variants below are ordered roughly from the familiar and widely played to the obscure and unusual, although related games are kept together where comparison is useful. The selection draws on variants played on modern sites, historical correspondence organisations such as NOST (kNights Of the Square Table) and AISE (Italian Association of Chess), and the stranger corners of chessvariants.com.

Chess variants had a rather different canon before the 2000s. Many games once played by correspondence societies disappeared when those organisations dissolved and never made the transition to modern playing sites. Some are also awkward for conventional Chess software because they require unusual interfaces or additional state. Part of the purpose of this collection is to preserve and revive some of that lost culture.

The list is therefore long, but every game on it is here for a historical, competitive, or some otherwise distinctive reason rather than to be a catalogue of variants.

The descriptions below assume familiarity with the rules and terminology of ordinary Chess, and generally cover only what is different and why it is interesting.

Unless otherwise stated, all variants use the fifty-move rule and threefold repetition.

===== Chess960 =====

https://en.wikipedia.org/wiki/Chess960
https://www.chess.com/terms/chess960
https://boardgamegeek.com/boardgame/12608/chess960

**Chess960**, also known as **Fischer Random Chess**, was formally introduced by Bobby Fischer in 1996. It randomises the pieces on the back rank while leaving the pawns in their usual positions. The two sides have mirrored setups, the bishops must start on opposite-coloured squares, and the King must start somewhere between the two Rooks. These restrictions give exactly 960 possible starting positions, including the standard Chess position (which is excluded in Abstract Play).

Castling is still allowed and can appear slightly unusual at first. Regardless of where the King and Rook begin, they end on the same squares as they would after castling in standard Chess: the King on the g-file and Rook on the f-file when castling towards the h-file, or the King on the c-file and Rook on the d-file when castling towards the a-file. All other pieces in between have to first be vacated.

This preserves almost all of the tactics and strategy of Chess while largely removing memorised opening theory. Familiar ideas such as development, King safety and pawn structure are still important, but players have to work out from the first move how the unusually placed pieces should cooperate.

It has since acquired a very strong institutional support for a Chess variant: FIDE incorporated Chess960 into the Laws of Chess in 2008 and sanctioned World Fischer Random Chess Championships in 2019 and 2022. It has more recently received renewed attention through high-level Freestyle Chess events involving many of the world's strongest players.

===== King of the Hill =====

https://www.chess.com/terms/king-of-the-hill

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**King of the Hill** adds an additional winning condition: you win immediately if your King reaches one of the four centre squares (d4, e4, d5 or e5) without being in check.

This gives the King a very active role. Players have to really control the centre instead of just occupy it with pawns and pieces, and the usually harmless King is a direct threat. The game tends to turn into races to escort or blockade (or to attempt to checkmate) the Kings.

===== Antichess =====

https://en.wikipedia.org/wiki/Losing_chess
https://www.chess.com/terms/giveaway-chess

**Antichess**, also known as **Losing Chess** or **Giveaway Chess**, is the more popular version of Chess with compulsory captures, but the objective of the game is reversed. You win by getting rid of all of your pieces, or by having no legal moves remaining.

The King has no royal status: there is no check or checkmate, the King may move into attacked squares and may be captured like any other piece. Castling is therefore not allowed.

Antichess has a really fun momentum because rather than forcing trades, you want to construct long chains of forcing sequences for the opponent to wipe out your pieces. Material advantage is a liability, and even very small endgames can be remarkably difficult to calculate. It has developed into one of the more seriously played and analysed Chess variants with extensive opening and endgame theory. The game has even been weakly solved: in 2016, Mark Watkins completed a [[https://magma.maths.usyd.edu.au/~watkins/LOSING_CHESS/LCsolved.pdf|computer-assisted proof]] that 1.e3 gives White a forced win. The solution is far too large to make ordinary human play trivial, however, and the variant continues to sustain a large competitive community.

===== Atomic Chess =====

https://en.wikipedia.org/wiki/Atomic_chess
https://www.chess.com/terms/atomic-chess
https://boardgamegeek.com/boardgame/240836/atomic-chess

In **Atomic Chess**, every capture causes an explosion. The capturing piece, the captured piece, and all pieces on the eight surrounding squares are removed. Pawns on surrounding squares are immune to the explosion, although a pawn is still removed if it is itself the capturing or captured piece.

A player wins by checkmating the opponent or by exploding their King. A move may never cause your own King to explode.

This changes the meaning of check considerably: attacking a piece adjacent to the King can be just as dangerous as attacking the King directly.

===== Crazyhouse =====

https://en.wikipedia.org/wiki/Crazyhouse
https://www.chess.com/article/view/crazyhouse-chess

In **Crazyhouse**, whenever you capture an opponent's piece, it changes colour and enters your **hands**. Instead of making an ordinary move, you may later **drop** one of the pieces in your hand onto an empty square. This is reminiscent of modern [[games:shogi|Shogi]].

Dropped pieces may give check or checkmate. Pawns may not be dropped onto the first or last rank, and a promoted pawn returns to being a pawn if it is captured. Pieces that are promoted from pawns are marked with a P in Abstract Play.

In Crazyhouse, material never really leaves the board, and a piece in your hand can suddenly appear almost anywhere. Drops can immediately fork pieces, block attacks or create elaborate checkmate patterns.

===== Hostage Chess =====

https://en.wikipedia.org/wiki/Hostage_chess
https://www.hostagechess.com/rules.html

**Hostage Chess** was invented by John A. Leslie in 1997. Captured pieces are not removed permanently but are kept in the capturing player's **prison**, and can be used to exchange for other pieces. Like Crazyhouse, captured material returns to play, but here it re-enters through negotiated exchange rather than being available directly.

Instead of making an ordinary move, you may rescue one of your pieces from the opponent's prison by releasing one of their pieces from your prison of equal or greater value (P < N / B < R < Q). Your rescued piece can immediately be dropped onto any empty square, while the piece you returned goes to your opponent's **airfield**. On a later turn, they may drop a piece from their airfield onto the board for free.

To make an exchange in Abstract Play, first select the opponent's piece from your prison to release it to their airfield, then select your piece from their prison, then choose the empty square where it is deployed. A piece already in your airfield can simply be selected and dropped. Pawns may not be dropped on the first or last rank. A dropped Pawn on its normal starting rank retains its double-step, and a Rook dropped onto its original corner retains castling rights.

Promotion is also tied to the prisons. A Pawn reaching the last rank must exchange places with one of its owner's Rooks, Bishops, Knights or Queens in the opponent's prison. If no such piece is there, the Pawn cannot move to the last rank and does not give check through that square.

Captures therefore create an economy rather than simply removing material. Taking a valuable piece gives you a powerful hostage to bargain with, but rescuing one of your own pieces necessarily gives something back to the opponent. The drops also make attacks increasingly dangerous as more material changes hands.

Hostage Chess acquired a particularly good reputation among Chess variant enthusiasts: in 1999, D. B. Pritchard called it the "variant of the decade".

===== Extinction Chess =====

https://en.wikipedia.org/wiki/Extinction_chess
https://www.chessvariants.com/winning.dir/extinction.html

**Extinction Chess** was invented by R. Wayne Schmittberger in 1985. Instead of checkmate, you win by making any one type of the opponent's pieces *extinct*, so Kings are not particularly special. Extinction means capturing a player's King or Queen, both Rooks, both Bishops, both Knights, or eliminating all of their Pawns. Pawns may promote to Kings.

Losing one Bishop or Knight leaves the remaining one extremely vulnerable. Promotion can in principle be used to save a piece type from extinction, but be wary of the number of pawns decreasing. There is a possibility of both players suffering an extinction on the same move with a pawn promotion, in which case, the player who made the move wins.

Since the King is not royal, it may move into attack and castling is allowed while in check or through attacked squares. The King and Rook must still be unmoved and the squares between them empty.

===== Anti-King Chess =====

https://www.chessvariants.com/diffobjective.dir/anti-king-chess.html
https://en.wikibooks.org/wiki/Chess_Variants/Anti-King_Chess

**Anti-King Chess** was created by Peter Aronson in 2002. In addition to the normal King, each player has an **Anti-King**, which moves like a King but must be under attack by the opponent at all times. If it is not attacked, it is in **anti-check**, and the player must make a move that puts it under attack again. If this is impossible, they lose.

The Anti-King cannot capture or be captured by enemy pieces, although it may capture friendly pieces. The ordinary King is still royal, so you are simultaneously trying to keep one King out of attack and the other one inside it.

This creates a very strange tension where enemy pieces can actually be useful because they keep your Anti-King safe. Attacking and defending are no longer opposites, and removing an opponent's attacking piece can sometimes put your own Anti-King in danger.

==== Anti-King I ====

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**Anti-King I** has a different starting setup in the corner, and all the Pawns are **Berolina Pawns**, which move diagonally and capture forwards (they are sometimes known as anti-pawns, which is fitting). They are shown as inverted Pawns. Since two of them can advance to the same square, their notation includes the starting file: `gf5` moves the g-pawn to f5, while a forward capture is written `fxf4`. There is no initial double-step or en passant. Castling is replaced by a one-time Knight leap available to an unmoved King or Anti-King.

The greater mobility of the Berolina Pawns makes it harder to simply seal an Anti-King permanently behind a blocked pawn structure, so the Anti-Kings tend to remain more relevant throughout the game.

==== Anti-King II ====

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</aprender></WRAP>

**Anti-King II** instead keeps the normal Chess pieces and rules, with the Anti-Kings added to the starting position right in front of each player's opponent d-pawn. It looks strange, but the Anti-King is relatively secure in this position and the game mostly proceeds as usual in the opening with the exception of the space blocked by it. This makes the idea easy to understand and preserves much of normal Chess strategy, while creating new questions about maintaining enemy attacks and exploiting blocked pawns as safe havens as the game progresses.

This version is more popular, likely because it is more familiar and allows players to explore the mechanic in isolation.

===== Racing Kings =====

https://www.chess.com/terms/racing-kings-chess
https://lichess.org/variant/racingKings

<WRAP center 300px><aprender>
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</aprender></WRAP>

**Racing Kings** was created by V. R. Parton in 1961. Both armies start together at one end of the board without Pawns, and the objective is to get your King to the eighth rank. Checks are completely forbidden. You may neither leave your own King attacked nor attack the opponent's King. For balance, if White reaches the eighth rank first, Black gets one final move to reach it as well and draw.

Unlike King of the Hill, this is a much purer racing game because checkmate is impossible. Your other pieces are used to clear routes for your own King and obstruct the opponent, while the prohibition on check creates some unusual invisible barriers around both Kings.

===== Three-check Chess =====

https://en.wikipedia.org/wiki/Three-check_chess
https://www.chess.com/terms/3-check-chess

In **Three-check Chess**, you may win either normally by checkmate, or by giving check to the opponent's King for the third time. Each move counts as at most one check, even if it is a double check.

Sacrifices that would be dubious in ordinary Chess can be worthwhile if they force one or two checks, and an exposed King can remain strategically vulnerable even when there is no immediate mating attack. The game strongly rewards initiative and attacking play.

===== Horde Chess =====

https://en.wikipedia.org/wiki/Dunsany%27s_chess
https://www.chess.com/terms/horde-chess
https://lichess.org/variant/horde

<WRAP center 300px><aprender>
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</aprender></WRAP>

**Horde Chess** was introduced by Filip Rachunek in 2002, based on the older Dunsany's Chess. In the version played on most websites, White has a horde of 36 Pawns but no King, while Black has the ordinary Chess army. White wins by checkmating Black, while Black wins by eliminating the entire horde, including any pieces created by promotion.

Black needs to get their pieces behind the one-directional horde to dismantle it, while White needs to preserve a connected advancing front to push through to promote and overwhelm the King.

===== Capablanca Chess and related variants =====

https://en.wikipedia.org/wiki/Capablanca_chess
https://samboy.github.io/ChessVariantResearch/

**Capablanca Chess**, from the 1920s, was an early attempt to "complete" the Chess army since the Queen combines Rook + Bishop movement, but the other two knight compounds are missing.

The board is extended to 10×8 to make space for the Bishop + Knight piece called the **Archbishop** (A) and the Rook + Knight piece called the **Chancellor** (C). These pieces have acquired many different names in later variants. To make it easier to move between games, we use Capablanca's final names and the notation A and C consistently throughout this family, while noting the traditional names used by each game. Note that Archbishop is also the name of [[https://www.chessvariants.com/piececlopedia.dir/archbishop.html|an unrelated fairy piece]].

Capablanca's original setup was:

''R N A B Q K B C N R''

Castling is extended to the wider board, with the King moving three squares towards the Rook. Pawns may also promote to the Archbishop or Chancellor.

The historical Capablanca setup has several commonly noted weaknesses, so it is not implemented here.

==== Gothic Chess ====

https://www.chess.com/terms/gothic-chess

<WRAP center 350px><aprender>
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</aprender></WRAP>


**Gothic Chess** was proposed by Ed Trice in 2000. It uses the same 10×8 board and pieces as Capablanca Chess, but rearranges the back rank to address weaknesses in Capablanca’s setup.

In particular, it avoids an initially undefended pawn, distributes the powerful diagonal-moving pieces more evenly, and produces cleaner development. [[https://www.samiam.org/chessv/Capa.html|Engine analyses]] also tend to find a somewhat smaller first-move advantage among the many different possible arrangements.

==== Grand Chess ====

https://www.mindsports.nl/index.php/arena/grand-chess
https://en.wikipedia.org/wiki/Grand_Chess
https://www.chessvariants.com/large.dir/freeling.html
https://boardgamegeek.com/boardgame/30596/grand-chess

<WRAP center 350px><aprender>
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**Grand Chess** was invented by Christian Freeling in 1984, and takes a different approach to introducing the complete army, this time on a square 10×10 board. He calls the Archbishop a **Cardinal** and the Chancellor a **Marshall**.

The Rooks start alone at the corners of the back rank, while the other pieces start on the second rank and the Pawns on the third to keep the same distance between the armies as ordinary Chess. Freeling perceived the difficulty of activating the Rooks to be [[https://www.mindsports.nl/index.php/arena/grand-chess/23-about-grand-chess|a problem]], and this was his solution to it, while also eliminating the need for castling, which he regarded as an ad hoc rule to solve that problem. Pawns may optionally promote on the eighth or ninth rank and must promote on the tenth, but they can only promote to one of their own previously captured pieces, which preserves what Freeling called [[https://mindsports.nl/index.php/moving-forward-looking-back|material completeness]] without being overly restrictive, since Grand Chess’s additional powerful pieces reduce the need to create extra Queens.

==== Seirawan Chess ====

https://www.seirawanchess.com/
https://www.chess.com/terms/seirawan-chess
https://boardgamegeek.com/boardgame/35574/seirawan-harpers-chess
https://www.chessvariants.com/rules/seirawanchess

**Seirawan Chess**, or **S-Chess**, was created by Yasser Seirawan and Bruce Harper in 2007, and is another approach to the complete army. Instead of extending the board, this is played on the conventional 8×8 board. Each player has an Archbishop and a Chancellor in reserve. In the original rules, the Archbishop is called the Hawk and the Chancellor the Elephant.

The board starts exactly as in standard Chess. When one of your back-rank pieces leaves its original square for the first time, you may **gate** one of the reserve pieces onto the square that was just vacated. Once all of your possible gating squares have been used or lost, any remaining reserve piece can no longer enter the game. Castling may also be used to gate one piece onto either of the two vacated squares.

This manages to introduce the two powerful Capablanca-style pieces without making the board any larger. More importantly, gating turns development into a timing decision. Moving a piece develops it while opening a one-time opportunity to introduce another piece.

==== Janus Chess ====

https://www.gnu.org/software/xboard/whats_new/rules/Janus.html
https://en.wikipedia.org/wiki/Janus_Chess
https://www.chessvariants.com/large.dir/janus.html

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**Janus Chess** was invented by Werner Schöndorf in 1978. It is played on a 10×8 board with two additional Pawns and two Archbishops called **Januses** on each side, keeping the setup symmetrical. There is no evidence that it is a Capablanca derivative, but it is similar enough that it is included in this family.

In the opening position, they start between the Rooks and Knights, and the King and Queen are reversed compared with ordinary Chess (probably to keep the Queen on her colour). Castling moves the King towards the edge, ending on the b- or i-file.

The Archbishop is particularly interesting because its two components compensate for one another: the Bishop provides long-range movement but is colour-bound, while the Knight can jump and switch colour complexes but has very short range. Having the same new piece on both wings also gives Janus Chess a simpler and more symmetrical character than the complete-army variants. The Archbishop is almost as powerful as a Queen but attacks in a very different way, so Knight forks and diagonal attacks become much more prominent.

Janus Chess developed a substantial competitive tradition in Germany's Saarland and the surrounding Saar-Lor-Lux region, including well-sponsored tournaments featuring prominent international grandmasters.

===== Knight Relay Chess =====

https://en.wikipedia.org/wiki/Knight_relay_chess
https://www.chessvariants.org/diffmove.dir/nrelay.html

**Knight Relay Chess** or **N-Relay Chess** was invented by Mannis Charosh in 1972. It is ordinary Chess except that Knights act as **relays** rather than conventional pieces.

Knights cannot capture or be captured, and do not give check. Instead, every friendly Pawn, Bishop, Rook, or Queen attacked by a Knight temporarily gains the ability to move and capture like a Knight in addition to its normal movement. Kings do not receive this ability. A move that uses the relayed power is written with an `R` suffix, such as `Bb3R` or `dxf4R`.

A Pawn may not use relayed movement to reach the first or eighth rank. If it returns to its normal starting rank, it regains its double-step. There is no en passant.

This makes the position of the Knights important. A Knight may be used as a blocking piece, and it can turn a Bishop into an Archbishop, a Rook into a Chancellor, or a Queen into an Amazon (Queen + Knight), and moving the Knight can give or remove these powers from several pieces at once. Even Pawns can make Knight leaps while they are being relayed, making the pawn structure more dynamic than in ordinary Chess.

Knight Relay Chess became one of the more popular variants played by NOST (the kNights Of the Square Table), an old correspondence chess-variant organisation. It was included by David Pritchard in //Popular Chess Variants// (2000).

===== Multimove Chess =====

These variants give a player more than one move decision per turn.

==== Duck Chess ====

https://www.chess.com/terms/duck-chess

**Duck Chess** was invented by Dr Tim Paulden in 2016. A neutral **duck** occupies one square of the board and cannot be captured. On every turn, you first make a Chess move and then move the duck to any empty square. The duck blocks movement through its square, although Knights can still jump over it.

There is no check or checkmate: Kings may be left attacked, and you win by actually capturing the opponent's King. This works because after exposing your King, you still have the second half of your turn to move the duck somewhere that blocks the attack.

The duck can block a recapture, cut off a Rook or Bishop, release a pin or suddenly protect an otherwise exposed King. The interesting part is that every turn consists of first changing the position and then deciding which single square you want to make unusable.

Duck Chess became particularly popular online in 2022 and was subsequently added to Chess.com, where it remains one of the better-known modern Chess variants.

==== Marseillais Chess ====

https://en.wikipedia.org/wiki/Marseillais_chess
https://www.chessvariants.org/multimove.dir/marseill.html

**Marseillais Chess** was first published in Marseille in 1925. Each player normally makes **two moves per turn**, and the same piece may be moved twice. If the first move gives check, however, the turn ends immediately. A player who begins their turn in check must escape it with their first move.

Abstract Play uses the modern **balanced** rule introduced by Robert Bruce in 1963, where White makes only one move on the first turn, after which both players receive two moves per turn.

As usual, moving twice can completely change the tactics. A piece can move into position and immediately attack, a Pawn can advance twice, or one piece can clear the way for another, so many combinations that normally require the opponent's cooperation can happen in a single turn.

==== Progressive Chess ====

https://en.wikipedia.org/wiki/Progressive_chess
https://www.chessvariants.com/multimove.dir/progressive.html
https://en.chessbase.com/post/new-year-s-present-progressive-chess

In **Progressive Chess**, White makes one move on the first turn, Black makes two moves, White then makes three, Black four, and so on. A player may move the same piece multiple times during their series. If you begin a series in check, you must escape it with your first move.

There are several rulesets, but most common are the **Italian** and the **Scottish** rules. Under Italian rules: you must use the full series, and may give check only on the final move, whereas under
Scottish rules, giving check immediately ends your series, even if you had moves left. For both, if you run out of legal moves on your turn, it is stalemate and it is a draw.

Abstract Play uses the **Italian rules** where checks may only be given on the last move because it became the most developed competitive form. It has the strongest tournament tradition, the largest body of recorded games and theory, and has been the main target of serious computer analysis. There are interesting chess compositions that exploit the fact that you cannot give a check until the final move (like forcing an underpromotion to avoid a check), but in practice, it is said that the two different rulesets rarely affect the outcome of the game.

==== Progressive Circe ====

https://www.chessvariants.org/index/subsection.php?itemid=CirceProgressive
https://unoscacchista.com/2025/12/17/chess-variant-scacchi-progressivi/
https://www.oocities.org/Colosseum/Lodge/2483/ann/a_regola.htm

**Progressive Circe** was proposed by Roberto Gravina in 1979. It combines [[https://en.wikipedia.org/wiki/Circe_chess|Circe]] with Italian Progressive Chess.

Turns follow the normal Italian Progressive rules. However, when a piece is captured, it is **reborn** on a fixed square determined by its type, colour, and the square where it was captured. Pawns return to their starting rank on the same file. Rooks, Bishops, and Knights return to the corresponding home square of the same colour as the capture square, while Queens return to d1 or d8. If the rebirth square is occupied, the piece is captured normally.

The two rules interact strongly. A piece that is captured may return in time to affect the rest of the same series, while occupying an opponent's rebirth square can make a capture permanent.

Progressive Circe developed a substantial following in the Italian chess-variant community. It became an official game of the **[[https://unoscacchista.com/2024/09/26/chess-variant-lassociazione-italiana-scacchi-eterodossi/|Associazione Italiana Scacchi Eterodossi (AISE)]]** in 1981 and was played extensively in tournaments and championships, with dedicated bulletins and opening analysis. Circe itself is much better known as a condition for Chess problems; the progressive form is unusual in having a substantial history as an actual played game.

==== Avalanche Chess ====

https://en.wikipedia.org/wiki/Avalanche_chess
http://www.chessvariants.org/mvopponent.dir/avalanche.html

**Avalanche Chess** was designed by Ralph Betza in 1977. After making your normal move, you must also move one of your opponent's Pawns one square forwards, if possible. You cannot capture with the opponent's Pawn. If you advance it to the promotion rank, your opponent chooses what it promotes to on their turn. There is no en passant.

With this rule, you can force an opponent's Pawn forwards to create weaknesses or get it out of your way, but sometimes every available Pawn move helps the opponent. It is possible to put your king in check then block it with your opponent's pawn, but if moving your opponent's pawn results in a check on your King, then you immediately lose the game.

Abstract Play uses **Balanced Avalanche Chess**, in which White does not push a Black Pawn after the first move of the game.

===== Triplets =====

https://www.chessvariants.org/multimove.dir/triplets.html

**Triplets** was invented by Adam Sobey in the 1980s. The game uses the normal Chess setup. On each player's first turn, they must move a Pawn. On their second turn, they must move a Pawn and a piece other than the King, in either order. From the third turn onwards, they must make three moves: one with a Pawn, one with a piece other than the King, and one with the King, in any order. All three moves form a single turn.

The King only needs to be out of check at the end of the turn. En passant may likewise be made at any point during the turn.

Castling counts as the King move, and the corresponding Rook move does not use the piece move. Queenside castling is impossible. A Pawn which promotes may use the piece move to move again immediately.

A player loses by checkmate or if they cannot make every required part of their turn. In practice, the usual way to win is to leave the opponent without a legal Pawn move. Pawn mobility is therefore a central resource, and material can be less important than in ordinary Chess.

Triplets saw tournament play in Britain, Italy and the United States before almost fading completely into obscurity.

===== Different setups and geometries =====

These variants mostly keep the ordinary rules of Chess but change the board geometry or starting position. Chess960 belongs to this family, but it is described above because it is probably the most important competitive variant.

==== Cylinder Chess ====

https://en.wikipedia.org/wiki/Cylinder_chess

**Cylinder Chess** is an old variant in which the left and right edges of the board are joined, so the a- and h-files are adjacent.

Pieces can move and attack across this boundary. For example, a Bishop can continue its diagonal off one side of the board and onto the other, while Pawns can capture across the edge. A Rook blocked by its own piece on one side of it can still reach the squares beyond by running the other way round. Castling works the same as in ordinary chess, and the rook travels along the first rank rather than around it.

In our implementation, a move must still change the position. Some rulesets allow null moves by moving a Rook or Queen right around the board and back, a device sometimes used to create zugzwang in Cylinder Chess problems.

The cylinder removes the usual distinction between centre and edge files. There are no left or right flanks, and pieces can attack around either side of the board. This also creates unusual tactics where the same square can sometimes be reached along two different paths.

==== Circular Chess ====

https://en.wikipedia.org/wiki/Circular_chess
https://web.archive.org/web/20080323091608/http://www.circularchess.co.uk/

<WRAP center 400px><aprender>
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</aprender></WRAP>

Modern **Circular Chess** was developed by David Reynolds in 1983. Pieces mostly move as they do in ordinary Chess. Each player's Pawns are divided into two groups moving in opposite directions. They otherwise move and capture like ordinary Pawns, and may make their initial double-step. A Pawn promotes after travelling six spaces from where it began. There is no castling or //en passant//, and as on the cylinder there are no null moves: on an otherwise empty ring a Rook or Queen may not make a full circuit back to the field it started on.

The circular geometry changes the relative strengths of the pieces quite dramatically. Rooks and Queens gain very long lines around the rings, while Bishops and Knights have fewer squares available than they do on an ordinary board. There are also no corners in which to trap a King, so several familiar basic checkmates no longer work.

==== Balbo's Game ====

https://en.wikipedia.org/wiki/Balbo%27s_game
https://www.chessvariants.com/shape.dir/balbo.html

<WRAP center 350px><aprender>
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</aprender></WRAP>

**Balbo's Game** was devised by G. Balbo in 1974. It uses the normal Chess pieces, minus one Pawn per side, on a 70-square diamond-shaped board.

Pawns promote on the furthest square of their file; on files c and i they may promote only to a Bishop or Knight, and they do not promote at all on the outermost files, so they are blocked until they can make a capture. There is no castling.

This board was created to give more importance to the Bishops, which are still colourblind but have a higher and more-consistent mobility than in normal Chess. Rooks can still move to more spaces, but their mobility is more limited when they are near the sides. The spread-out initial position also leaves many exploitable gaps, making the opening particularly sharp.

==== Troitzky Chess ====

https://www.mayhematics.com/s/reshap.htm
https://mats-winther.github.io/bg/troitzkychess.htm

<WRAP center 350px><aprender>
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</aprender></WRAP>

**Troitzky Chess** was proposed by Paul Byway in 1997, with the alternative starting position suggested by George Jelliss, in which every Pawn begins defended.

It is played with the normal Chess army on a near-circular board, which is built by removing the corner squares on the usual 8×8 board, and adding two small extensions in each side.

Pawns promote on the furthest square of whatever file they occupy. Since the outer files are much shorter, capturing towards the edge can dramatically shorten a Pawn's route to promotion. There is no castling.

This looks similar to Balbo's Game, with the Bishops and Knights having slightly more mobility than in ordinary Chess. The board was originally inspired by the unusual fact that King and two Knights can force mate against a lone King on this geometry ([[https://en.wikipedia.org/wiki/Two_knights_endgame#Troitsky_line|Troitzky line]]).

==== Legan Chess ====

https://en.wikipedia.org/wiki/Legan_chess

<WRAP center 300px><aprender>
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</aprender></WRAP>

**Legan Chess** was devised by the Frenchman L. Legan in the early 20th century. It uses the normal Chess board and pieces, but the two armies are arranged around diagonally opposite corners.

Pieces move normally except for Pawns. White Pawns move one square diagonally upwards and to the left, and capture one square upwards or to the left; Black Pawns move and capture in the opposite directions. There is no initial double move, castling, or en passant.

Pawns promote on the seven squares forming the far corner: a5–a8 and b8–d8 for White, and e1–h1 and h2–h4 for Black.

The result is essentially Chess played along a diagonal axis, with the armies advancing from corner to corner.

==== Viking Chess ====

https://www.chessvariants.org/large.dir/contest84/vikingchess.html

<WRAP center 500px><aprender>
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**Viking Chess** was designed by Tomas Forsman and is played on a 12×7 board. Instead of facing each other, the two armies begin side-by-side at the same end of the board, and both sides' Pawns move in the same direction towards the seventh rank. There is no castling, pawn double-step or en passant.

The armies begin in immediate contact from the side while their Pawns race in parallel towards promotion. The rooks are not blocked so they may be used to defend the spaces to prevent White from gaining a huge advantage by marching their pawns immediately. The game is said to be very sharp and aggressive.

This should not be confused with [[games:tafl|Hnefatafl]], which is also frequently marketed under the name "Viking Chess".

===== Changing pieces =====

In these variants a piece's identity is not fixed for the game. A piece can be remade off the board, earn new movement as it plays, or transform.

==== Pocket Mutation Chess ====

https://en.wikipedia.org/wiki/Pocket_mutation_chess
http://www.chessvariants.org/large.dir/pocketmutation.html

**Pocket Mutation Chess** was invented by Mike Nelson in 2003. Each player has a **pocket** that can contain one of their own pieces. Instead of moving, you may choose one of your pieces other than the King, optionally **mutating** it into another piece, before putting it in your pocket. On a later turn, the piece can be dropped back onto any empty square except for squares in the last rank. White may not use the pocket on the first move, and there is no castling.

The pieces are divided into classes. Mutation occurs within a class, but if it is pocketed in the last rank, it will go up a class. A Pawn that reaches the last rank stays put as a Pawn until it is pocketed in this way. Rather than requiring a glyph for every piece to be memorised, we name the pieces compositionally, so the letters tell you how the piece moves.

The pieces are combinations of the ordinary Chess pieces and the **Nightrider** (NN), which repeats Knight leaps in the same direction while the landing squares are empty. An **S** prefix adds a King step and makes a **Super** piece, so SB is a Bishop + King step, SBN a Bishop + Knight + King step, and SBNN a Bishop + Nightrider + King step. The classes are:

  * **Class 1:** P (**Pawn**).
  * **Class 2:** B (**Bishop**); N (**Knight**).
  * **Class 3:** R (**Rook**); NN (**Nightrider**) ; SB (**Super Bishop**).
  * **Class 4:** BN (**Archbishop**); SR (**Super Rook**).
  * **Class 5:** Q (**Queen**); RN (**Chancellor**); BNN (**Archbishop Rider**); SBN (**Super Archbishop**).
  * **Class 6:** RNN (**Chancellor Rider**); SRN (**Super Chancellor**); SBNN (**Super Archbishop Rider**).
  * **Class 7:** QN (**Amazon**); SRNN (**Super Chancellor Rider**).
  * **Class 8:** QNN (**Amazon Rider**).

The pocket gives you a way to temporarily remove an awkward piece, change what it does, and redeploy it somewhere completely different. The fairy pieces therefore enter the game as strategic choices rather than simply being dumped into an enlarged starting army.

The pieces should be self-explanatory, with the compound Knight glyphs. For Nightrider movement, a cross is drawn behind it, and for a combination with a King step a circle is drawn behind it.

To use the pocket, select a piece once to see its ordinary moves and select it again to pocket it. If its class offers several mutations, select the piece you want from the panel that appears.

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==== Way of the Knight ====

https://www.chessvariants.com/old.dir/wotn.html
https://gambiter.com/chess/variants/Way_knight.html

**Way of the Knight** is Chess with RPG elements, invented by Ralph Betza. It begins as an ordinary game of Chess, but every piece is also an adventurer who may advance through eleven levels. The ordinary pieces begin at the levels: Pawns at level 1, Knights and Bishops at level 3, Rooks at level 5, Queens at level 8 and the King at level 11.

A piece must improve by exactly one level whenever it captures a piece whose level is at least half its own. A piece in one of the first three levels also improves when it reaches relative rank six, seven or eight respectively.

There are two versions of the advancement tree. In the **original game**, choices occur only after levels one, five and seven; otherwise the path is forced. **Complete Paths** fills in the gaps, allowing an adventurer to remain aligned with its current path or move towards the neutral path as it develops. The additional pieces in Complete Paths are highlighted below.

^ Level ^ Original ^^^ Complete Paths ^^^
^ ::: ^ Knight's path ^ Neutral path ^ Bishop's path ^ Knight's path ^ Neutral path ^ Bishop's path ^
| 1 | | P | | P | P | P |
| 2 | WfbD | | DA | WfbD | | DA |
| 3 | N | | B | N | | B |
| 4 | NW | | BD | NW | KD | BD |
| 5 | | R | | NWfbD | R | FAD |
| 6 | NN | | FLD | NN | KAD | FLD |
| 7 | | NB | | NAD | NB | BL |
| 8 | RN | | Q | RN | | Q |
| 9 | | BNN | | | BNN | |
| 10 | | RNN | | | RNN | |
| 11 | | K | | | K | |

In the original game, the neutral path branches after levels one, five and seven, giving exactly three decisions. Otherwise an adventurer continues along its existing path whenever possible and joins the neutral path when that path ends.

In Complete Paths, an adventurer on the Knight's or Bishop's path may remain on that path or move to the neutral path, but may not cross directly to the opposite path. A neutral adventurer may choose any path available at the next level.

The unfamiliar letters describe these movements:

  * ''W'' — one square orthogonally, in a + shape; traditionally called the Wazir.
  * ''F'' — one square diagonally, in an × shape; traditionally called the Ferz.
  * ''D'' — a two-square orthogonal leap, the Dabbaba.
  * ''A'' — a two-square diagonal leap, the Alfil.
  * ''L'' — a 1×3 leap, Betza's Long Knight, now usually called the Camel or sometimes the Giraffe.
  * ''NN'' — the Nightrider, which repeats Knight leaps in the same direction.

''N'', ''B'', ''R'', ''Q'' and ''K'' have their ordinary Chess meanings. Letters simply combine their movements, so ''NW'' is Knight + Wazir and ''BD'' is Bishop + Dabbaba. Lower-case direction letters restrict the move that follows them, so ''fbD'' means only the forward and backward Dabbaba leaps. The Dabbaba, Alfil, Knight and Long Knight are leaps, so intervening pieces do not matter.

The paths have some geometric logic behind them. From levels two to seven, the Bishop's path is colour-bound. The Long Knight's 1×3 leap stays on the same colour, allowing these pieces to reach beyond a Bishop's diagonals without losing that character. The Knight's path instead develops pieces that are free to move between the two colours. ''NB'' is the familiar Bishop + Knight Archbishop, while ''RN'' is the Rook + Knight Chancellor.

The final improvement creates another King. While a player has more than one King, they may leave one in check or allow it to be captured; once only one remains, the ordinary rules of check and checkmate protect it. In theory, a legal improvement of an ''RNN'' into a second King may therefore also be used to escape check.

Abstract Play uses consistent visual indicators for the compound pieces. A round-headed body is a neutral stepper: a plus on it is the Wazir's orthogonal steps, a cross is the Ferz's diagonal steps, and both marks together means it moves like a King. Arrowheads around a piece show the directions of its Dabbaba or Alfil leaps. ''DA'', which has no stepping mave is drawn with a circle in the middle.

When a piece also gains Knight movement, the usual compounds are used. For combinations without a compound glyph, we simply stack the piece over the Knight for now (until someone is helpful enough to create a better SVG glyph for us...). If it combines with a long Knight, it is drawn over a Giraffe (its long neck should evoke the idea the 1-3 step leaper), as with ''FLD'' and ''BL''. A large X behind a piece changes its Knight movement into Nightrider movement, allowing the piece to continue making Knight moves so long the landing square is empty.

^ Way of the Knight ^ Complete Paths ^
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==== Jabberwocky Chess ====

https://www.chessvariants.com/rules/jabberwocky-chess
https://www.chess.com/blog/Pokshtya/jabberwocky-chess

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**Jabberwocky Chess** was invented by Vadrya Pokshtya in 2024. Each player begins with sixteen Kings filling their first two ranks, but every piece changes identity after it moves according to the cycle **King → Pawn → Knight → Bishop → Rook → Queen → King**. Thus, moving a King creates a Pawn, moving that Pawn creates a Knight, and eventually moving a Queen creates another King.

There is no check and Kings may be captured like ordinary pieces, but a player must have at least one King remaining at the end of every turn. Captures are compulsory whenever one is available. Pawns move only one square forwards, and when a King turns into a Pawn on the farthest rank, it promotes to a Knight, Bishop, Rook or Queen of the player's choice.

The transformation cycle makes the identity of every piece temporary. Moving a powerful Queen also turns it into the King you may need to survive. Compulsory captures make this especially tactical because an opponent can force a piece to move and therefore force it to transform.

===== Reincarnation Chess =====

https://en.wikipedia.org/wiki/Philip_M._Cohen#Reincarnation_Chess

**Reincarnation Chess** was developed by Philip M. Cohen in 1966 from his earlier Zombie Chess. It seems to be a variant that has been largely forgotten.

When a piece captures another piece, the captured piece is not gone permanently. Once the capturing piece later leaves that square, a **zombie** of the captured piece appears there, belonging to the player who made the capture.

Ordinary pieces can capture only ordinary pieces, while zombies can capture only zombies. Pieces of the two kinds cannot capture or move through one another, however, so zombies can act as obstacles to the ordinary game. When a zombie captures another zombie and later leaves the capture square, the captured piece is reincarnated as an ordinary piece, again belonging to the capturing player.

Zombie Pawns promote to zombie pieces and pieces that are reborn on the player's starting square get the starting privileges, like the Pawn double-step and castling rights with an unmoved King. If several successive captures happen on one square before the occupying piece leaves, only the last captured piece determines what appears. There is no en passant.

Reincarnation Chess was played in NOST correspondence tournaments. Michael Keller described it in //World Game Review 10// as the best of Cohen's family of zombie variants.

===== Two boards =====

These variants are played across two boards at once, with pieces moving between them.

==== Alice Chess ====

https://en.wikipedia.org/wiki/Alice_chess
https://www.chessvariants.com/other.dir/alice.html

**Alice Chess** was invented by V. R. Parton in 1953 and is played using two 8×8 boards. Both armies begin normally on the first board, with the second board empty.

A piece makes an ordinary Chess move on the board that it currently occupies, but after the move it is transferred to the corresponding square on the other board. That corresponding square must be empty. Captures take place before the transfer, so you can only capture a piece that is on the same board as the moving piece.

The rule is simple but it can be difficult to visualise. Pieces continually disappear from one board and reappear on the other, making blocking slightly complicated. The game is particularly well suited to a digital implementation where the two layers can be displayed on the same board, since each square can only hold at most one piece on either board.

In **Alice Chess II** or **Looking-Glass Alice Chess**, listed here as **Alice Chess (armies apart)**, Black begins on the second board instead of the first. The armies therefore start in separate worlds and must cross into one another's before they can make contact.

==== Dimension X ====

https://www.chessvariants.com/rules/dimension-x

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**Dimension X** was invented by Gary K. Gifford in 2006 and dedicated to the memory of H. P. Lovecraft.

The game uses two ordinary chessboards. Chess pieces remain on the upper board, while each player has a **Spider**, **Spitting Cobra**, and **Crab** in the lower **Dimension X**. Creatures may move between corresponding squares of the two boards.

Squares in Dimension X are written with capitals: **B2** lies beneath **b2**. Within Dimension X, the Spider and Crab move one square in any direction, while the Cobra moves one or two squares along a line. Creatures block but cannot attack one another.

A creature may surface only within the central 6×6 area. Once on the upper board it cannot move there, and may only return to Dimension X. It can be captured normally by chess pieces, and its powers may affect pieces on the outer ranks and files.

  - The Spider webs every adjacent enemy piece except another Spider. Webbed pieces cannot move or use creature powers.
  - The Spitting Cobra may remove an enemy piece one or two squares away along a rank, file, or diagonal, provided nothing intervenes. Creatures may also be targeted.
  - The Crab may pinch an adjacent enemy piece to any (other) empty square on that piece's own first rank. If no such square exists, it is destroyed. Creatures are always destroyed when pinched. Any piece caught in the web of a Spider is also destroyed.

Each turn consists of a compulsory Chess move and up to one move or action with each creature, in any order. A creature may either move or use its power, but not both.

There is no check or checkmate. The game is won by removing the opposing King. A player who cannot make a Chess move loses unless they can capture the opposing King on that move.

Abstract Play introduces the creatures gradually to reduce White's first-move advantage: White's first turn uses no creatures, Black's first allows one, White's second allows two, and from Black's second turn onward all three may be used.

===== Co-Chess =====

**Co-Chess** is a family of variants invented by Ralph Betza in 1973 and inspired by the Coordinator in [[games:Ultima|Ultima]].

Two pieces of the same colour that are of the same kind form a **co-pair**: two Rooks, two Bishops, two Knights or two Queens. Each Queen also forms a co-pair with the King. A Rook and a Knight are two pieces and not a pair, and Pawns form no co-pairs at all.

When one member of a co-pair moves so that the two pieces are on different ranks and files, the other two corners of the rectangle become **co-squares**. For example, when the Rook moves from c1 to c2 below, it forms co-squares with the Rook at a1 at positions a2 and c1. What happens to pieces on the co-squares depends on the variant.

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A moving piece forms co-squares with every piece with which it can form a co-pair. With three Rooks, for example, moving one may create up to four co-squares. Promotion and conversion can therefore create additional co-pairs, although promotion itself does not create co-squares.

Co-squares exist only for the move that creates them, and their effects are compulsory. Co-effects do not themselves create further co-squares.

Castling counts as moving both the King and Rook, and either piece may therefore create co-squares. A move is legal if the position is legal after all co-effects have been applied. The King may even move into or through check if the co-effect removes the attack before the move is complete.

The three most successful Co-Chess variants were Conversion Chess, Transportation Chess and Overloader/Restorer Chess. They are presented here in the order used by //Popular Chess Variants//.

==== Transportation Chess ====

**Transportation Chess**, or **Transchess**, was invented by Ralph Betza in 1973.

Every non-King piece on a co-square must be **transported** to another square chosen by the player. All transportations are simultaneous. Transported pieces may exchange squares, and the square vacated by the piece that created the co-squares is also available.

A Pawn cannot be transported to its eighth rank. A Pawn transported to its first rank moves and captures normally, and any Pawn on its second rank may make a double move, even if it has moved previously.

An original Rook that has not moved under its own power retains its castling rights if it is transported away and later returned to either Rook starting square.

Transportation was one of NOST's twenty leading variants. Games tend to be short and highly tactical.

==== Conversion Chess ====

https://www.chessvariants.com/other.dir/conversion.html

**Conversion Chess** was invented by Ralph Betza in 1973.

An enemy piece on a co-square changes sides. Friendly pieces on co-squares are unaffected. Converted pieces may form new co-pairs on later moves.

A threat to convert the King is check, and an unavoidable threat is checkmate. Ordinary captures, check and checkmate also apply.

==== Overloader/Restorer Chess ====

https://www.chessvariants.com/other.dir/orchess.html

**Overloader/Restorer Chess**, usually shortened to **O/R Chess**, was invented by Ralph Betza in 1974.

An enemy piece on a co-square becomes **overloaded**. A friendly overloaded piece on a co-square is instead restored to full power. Other friendly pieces and enemy pieces that are already overloaded are unaffected.

An overloaded piece retains its normal movement but cannot capture, give check, castle or form a co-pair. An overloaded Pawn also loses its double move and cannot promote. Overloaded pieces may be captured normally.

The effect lasts until the piece is restored. A Pawn restored on its eighth rank promotes immediately.

In Abstract Play, an overloaded piece is marked by a coloured disc.

===== Pushing and pulling =====

These variants let a move displace other pieces around the board, either alongside ordinary captures or in place of them.

==== Magnetic Chess ====

https://www.chessvariants.org/other.dir/magnetic.html
https://jpneto.github.io/chess_variants/magnetic.htm

**Magnetic Chess** was invented by João Pedro Neto and Claude Chaunier in 1996. Pieces move as in normal Chess, but each non-King move also produces a **magnetic effect**.

From the destination square, the nearest piece in each orthogonal direction is affected. A friendly piece is **repelled** as far away as possible, while an enemy piece is **attracted** to the adjacent square. Kings are neutral: they neither cause nor undergo magnetic movement, and block magnetic effects.

There is no check or checkmate; the objective is to capture the opposing King. There is no //en passant//. When castling, the Rook produces the magnetic effect. A Pawn on either of its first two ranks may make a double step.

Magnetic Chess appeared in //NOSTalgia// and //Variant Chess// soon after its invention, and was included in David Pritchard's //Popular Chess Variants// (2000), despite the game being only a few years old at the time.

==== Highcastle Chess ====

https://www.chessvariants.com/diffmove.dir/highcastle.html

**Highcastle Chess** was invented by Ed Pegg Jr. in 1988. It was subsequently played by NOST, including in a postal championship that year. It generalises the displacement involved in castling to arbitrary pairs of pieces.

Instead of making a normal Chess move, a player may highcastle. Choose one of your own pieces and another piece of either colour on the same rank, file or diagonal. There must be at least two empty squares between them, with no intervening pieces.

The first piece moves two squares towards the second. The second piece is then moved to the square which the first piece passed over. For example, with a White Pawn on e2 and a Black Pawn on e7, White may highcastle them by moving the White Pawn to e4 and the Black Pawn to e3.

Any pieces may take part, not only the King and Rook, and they need not be unmoved. A King may pass through attacked squares while highcastling, and a checked King may escape by highcastling. The opposing King may also be moved by a highcastle, including into check. Highcastling itself never captures a piece.

Ordinary moves and captures remain legal, but en passant is not. A Pawn returned to its own second rank by a highcastle regains its initial two-square move.

In Abstract Play, clicking on your own piece once shows its ordinary moves. Clicking on it again shows the available highcasting moves.

==== Dynamo Chess ====

https://www.chessvariants.com/mvopponent.dir/dynamo.html
https://en.wikipedia.org/wiki/Dynamo_chess (seems to have rule errors at the time of writing)

**Dynamo Chess** was invented by Hans Klüver and Peter Kahl in 1968. Pieces move as in normal Chess, but captures are replaced by pushing and pulling. The description of the rules is lengthy, but they are rather clear when seen on the board (try it in the Playground).

A piece may use its normal movement to push or pull one other piece, friendly or enemy. Sliding pieces exert force along their normal lines, while Knights do so by Knight leaps. The two pieces move in the same direction, although the forcing piece may remain stationary if pushing. Pieces other than the King may also move off the board; when pulling another piece off, the pulling piece must leave with it.

Pieces leave play by going off the board, whether under their own power or by being pushed or pulled. Pawns can push but not pull: they push friendly pieces forwards and enemy pieces diagonally. A Pawn on its second rank has its double step even if it has previously moved. A Pawn reaching its final rank by any means promotes, with the player causing the promotion choosing the piece. En passant is not used.

The King is in check when it can be forced off the board. A push or pull may not move a King directly into or through check, but a Dynamo move may nevertheless give check by creating a new threat against the enemy King. A push or pull may not be used to escape check, so you must respond to a check with an ordinary Chess move.

Castling is an ordinary Chess move and cannot be combined with a push or pull. The King may not castle out of, through, or into check. A King or Rook that has been displaced by Dynamo force may still castle if returned to its original square, provided it has never moved under its own power; merely exerting force while remaining stationary does not remove castling rights.

A Dynamo move may not restore the position that existed before the opponent's previous move.

In the Abstract Play interface, a dynamo move requires four steps:

  - Click on the piece to be moved.
  - Click on the piece to be pushed or pulled.
  - Click on the square to push or pull the second piece to, or click on the buffer to push or pull it off the board.
  - Click on the square to move the first piece to (it may remain on the current square if pushing), or click on the buffer to move it off the board as well.

Dynamo developed from Fred Galvin's Push Chess of 1967, adding pulling and allowing a piece to exert force without moving. It became an established NOST variant, appearing among NOST's Top Twenty and on its annual tournament schedule.

===== Belarusian Chess =====

https://belarus.fmjd.org/modules/publisher/item.php?itemid=212
https://plus.gambler.ru/tavlei/other/other_6.htm
https://www.chessvariants.org/crossover.dir/byelorussian.html

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**Belarusian Chess** was developed by Nikolai Grushevsky and Pyotr Shkludov in the 1980s. It combines Chess with [[https://en.wikipedia.org/wiki/Russian_draughts|Russian Draughts]].

Each side has a King, Queen, Rook, Bishop, Knight, eight Pawns, and eleven draughtsmen. The draughtsmen occupy the dark squares of the first three ranks, except for the King's square, while the Pawns occupy the remaining squares of the second and third ranks. The armies are arranged by rotation rather than reflection, with White's King on e1 and Black's on d8. Pawns on the second rank may take their double-step move, and en passant is allowed.

Chess pieces move normally. Draughtsmen follow Russian Draughts rules: they move diagonally forwards, capture forwards or backwards, may make multiple jumps, and promote on the last rank to long-ranging kings, or //damki//.

**Draughts captures are compulsory** and take priority over ordinary Chess moves. If several captures are available, any may be chosen; the longest is not compulsory.

The two kinds of piece can capture each other. Chess pieces capture normally, while draughtsmen capture Chess pieces by jumping over them. A compulsory draughts capture may prevent a player from answering check, and even the two Kings may sometimes stand next to one another when a capture elsewhere is forced.

The game grew out of Chess–Draughts problems published in Belarus from 1985, and was developed into a playable game by 1989.

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The **Shabel** variant was created by Leonid Samutin in 1993 as a more symmetric development of Belarusian Chess because he thought the original arrangement was too artificial.

The normal Chess back rank is restored, but there are no Pawns. Instead, the second and third ranks are completely filled with draughtsmen. Castling is allowed.

All other rules are the same. Since draughtsmen remain on one square colour, the light- and dark-square men form two interwoven systems connected by the Chess pieces.

The name //Shabel// comes from the Russian //ШАхматы и ШАшки БЕЛорусские// (Chess and Belarusian Draughts). Samutin later wrote that he had almost forgotten about Shabel, only to discover years later that it was still being played and that international tournaments were being held for it.