| 1 | p.boxed |
| 2 | | The capture of an enemy piece produces a new "checkered" piece belonging |
| 3 | | to both players. |
| 4 | |
| 5 | figure.showPieces.text-center |
| 6 | img(src="/images/pieces/Checkered/cp.svg") |
| 7 | img(src="/images/pieces/Checkered/cr.svg") |
| 8 | img(src="/images/pieces/Checkered/cn.svg") |
| 9 | img(src="/images/pieces/Checkered/cb.svg") |
| 10 | img(src="/images/pieces/Checkered/cq.svg") |
| 11 | figcaption Checkered pieces, born after captures. |
| 12 | |
| 13 | p Note: the initial French name for this variant is "l'Échiqueté". |
| 14 | |
| 15 | p The game potentially evolves in two stages. |
| 16 | |
| 17 | h2.stageDelimiter Stage 1 |
| 18 | |
| 19 | h3 Basics |
| 20 | |
| 21 | ol |
| 22 | li |
| 23 | | Each capture produces a new piece, taking on nature of |
| 24 | | the capturing or captured one. |
| 25 | li |
| 26 | | The new piece arising from a capture has a new color: |
| 27 | | "checkered", as illustrated above. |
| 28 | li |
| 29 | | All checkered pieces belong to the player in turn and can |
| 30 | | capture the opponents pieces. |
| 31 | |
| 32 | p Remarks: |
| 33 | ul |
| 34 | li. |
| 35 | A non-capturing checkered move cannot be "undone" right after since |
| 36 | this would repeat the same position. |
| 37 | li Checkered pieces cannot be captured. |
| 38 | |
| 39 | figure.diagram-container |
| 40 | .diagram |
| 41 | | fen:2kr4/pp6/2p5/4ss1r/1P2ns1P/2Np4/P1P1P1BP/R2o1RK1: |
| 42 | figcaption. |
| 43 | Black plays Rxh4=P. (Checkered pawn to) h5 is allowed then, |
| 44 | because piece's nature changed. |
| 45 | |
| 46 | h3 Pawns |
| 47 | |
| 48 | ul |
| 49 | li. |
| 50 | Pawns can jump two squares only from their initial rank, and only once in |
| 51 | the game. A checkered pawn keeps this right if the starting pawn |
| 52 | did not use it. |
| 53 | li. |
| 54 | Checkered pawns cannot capture en passant, because while the pawn was |
| 55 | "passing" they were of the same color. |
| 56 | |
| 57 | h3 Stalemate or checkmate? |
| 58 | |
| 59 | p. |
| 60 | The following diagram seems to show a mating pattern, but the king if |
| 61 | "attacked" by a checkered pawn – which still belongs to white. |
| 62 | Therefore, it can be considered that it's not really a check because |
| 63 | white is unable to "give back the turn". |
| 64 | Without the black bishop on a7 it would be mate (without debate), because |
| 65 | the king could virtually go to g1 before being captured by the |
| 66 | chameleon pawn. |
| 67 | |
| 68 | figure.diagram-container |
| 69 | .diagram |
| 70 | | fen:7k/b5pp/8/8/8/8/6ss/7K: |
| 71 | figcaption After 1...g2+(#?) |
| 72 | |
| 73 | p. |
| 74 | The interface considers that it's mate in both cases, following the idea |
| 75 | "it's checkmate if we cannot move, and the opponent on its turn could |
| 76 | take the king" (maybe after an impossible move). |
| 77 | |
| 78 | h2.stageDelimiter Stage 2 |
| 79 | |
| 80 | p.italic. |
| 81 | This stage can be disabled by unselecting "With switch" at game creation. |
| 82 | |
| 83 | p. |
| 84 | During the game one of the two players can decide to take control of the |
| 85 | checkered pieces. |
| 86 | They thus become autonomous and vulnerable to being captured - stage 2 |
| 87 | begins. The other player is in charge of both the white and black pieces, and |
| 88 | tries to eliminate checkered pieces. |
| 89 | The checkered side wins by checkmating either the white or black king. |
| 90 | |
| 91 | p. |
| 92 | To take the checkered pieces, play a move that "takes opponent's king" with |
| 93 | your king, and then execute a move. This is possible only if no such move |
| 94 | can capture a king. |
| 95 | |
| 96 | h4 Variant of stage 2 (unimplemented) |
| 97 | p. |
| 98 | An observer could decide to join the game by taking the checkered pieces |
| 99 | at any moment. |
| 100 | It then becomes a chess game with three players, with some subtelties to be |
| 101 | resolved. It was tested in some (real life) games organised by the variant |
| 102 | inventor. |
| 103 | |
| 104 | h3 Special moves |
| 105 | |
| 106 | p Checkered pawns can... |
| 107 | ul |
| 108 | li move and capture in either direction; |
| 109 | li take en passant, |
| 110 | li be promoted on either the first or eighth row. |
| 111 | |
| 112 | h3 Credits |
| 113 | |
| 114 | ul |
| 115 | li. |
| 116 | The rules of Checkered Chess were thought up by Patrick Bernier and |
| 117 | developed with the help of Benjamin Auder around 2011-2012. |
| 118 | li. |
| 119 | Thanks also to Olive Martin, Christian Poisson, Bevis Martin, Laurent |
| 120 | Nouhaud and Frédéric Fradet. |