| a | b | c | d | e | f | g | h | ||
| 8 |              | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
Losing chess[a] is one of the most popularchess variants.[1][2] The objective of each player is to lose all of theirpieces or bestalemated, that is, amisère version. In some variations, a player may also win bycheckmating or by being checkmated.
Losing chess wasweakly solved in 2016 by Mark Watkins as a win for White, beginning with 1.e3.
The rules are the same as those for standardchess, except for the following special rules:
Draws byrepetition,agreement, or thefifty-move rule work as in standard chess. Positions when neither player can win are also draws: for example, when the only pieces remaining arebishops of opposite colors. (This is similar to the dead position rule in standard chess.)
The origin of the game is unknown, but believed to significantly predate an early version, namedtake me, played in the 1870s.[3] Because of the popularity of losing chess, several variations have spawned. The most widely played (main variant) is described inPopular Chess Variants byD. B. Pritchard. Losing chess began to gain popularity in the 20th century, which was facilitated by some publications about this variant in the UK, Germany, and Italy.
In September 1998, what was known as the "first International Losing Chess Meeting" was held in Geneva, Switzerland, courtesy of Fabrice Liardet, recognized through a tournament held there as the strongest Losing Chess player in the world at the time. Indeed, there were many international players, including the Netherlands, United Kingdom, France, as well as Switzerland.[4]
Losing chess gained a new surge in popularity at the turn of the 20th and 21st centuries as an online game, thanks to the implementation of this variant onFICS in 1996, which greatly contributed to the popularization of losing chess.[5] International tournaments were held in 1998 and 2001.[4][6] As of 2022, the International Antichess Federation hosts annual international tournaments in Amsterdam.[7]
The internet chess serverLichess facilitates play of the game, referring to it as "antichess";[5] after regular chess it is the most popular variant on the site in terms of numbers of games played weekly.[8] Since 2018 the site has hosted an annual "Lichess World Championship" for the variant.[5][9]Chess.com also added this variant to their server, calling it "giveaway."[10]
Because of the forced capture rule, losing chess games often involve long sequences offorced captures by one player. This means that a minor mistake can doom a game. Such mistakes can be made from the very first move—it is currently known that a Black win can be forced after 13 of White's 20 legal opening moves.[11][12] Some of these openings took months of computer time to solve: they vary greatly in difficulty.
In the table below, green marks winning first moves for White; red marks losing first moves; and yellow marks moves that are not yet solved.
| Na3 | Nc3 | Nf3 | Nh3 | ||||
| a4 | b4 | c4 | d4 | e4 | f4 | g4 | h4 |
| a3 | b3 | c3 | d3 | e3 | f3 | g3 | h3 |
This main variant of losing chess wasweakly solved in October 2016; White is able to force a win beginning with 1.e3.[13] This solution is valid for both FICS and "International" rules on stalemate. Some lines are trivial (1...d6, 1...d5, 1...Na6, and 1...g6 lose in less than 20 moves), others are quite simple (1...Nf6, 1...h6, 1...e5, 1...f5, 1...h5, 1...f6, 1...a6, 1...a5 lose in less than 30 moves, subject to knowledge of the theory[14]), and some are quite complicated (1...Nh6, 1...Nc6, 1...c6, the win in which may require about 60 moves[14]). The most difficult are the following five openings[15] (in order of increasing difficulty): 1.e3 g5 (Wild Boar Defence), 1.e3 e6 (Modern Defence), 1.e3 b5 (Classical Defence), 1.e3 c5 (Polish Defence), and 1.e3 b6 (Liardet Defence).
David Pritchard, the author ofThe Encyclopedia of Chess Variants, wrote that the "complexity and beauty" of losing chess is found in itsendgame. He noted that, in contrast to regular chess, losing chess endgames with just two pieces require considerable skill to play correctly, whereas three- or four-piece endgames can exceed human capacity to solve precisely.[16] For example, the following endgames may turn out to be quite complicated:2 Knights vs Rook,3 Kings vs King, orBishop+Knight+King vs King.[17][18] In the latter case, in particular, a win may require more than 60 moves, which means that it is sometimes unattainable due to thefifty-move rule.
| a | b | c | d | e | f | g | h | ||
| 8 | | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
Implementations of the main variant can vary in regard to stalemate.[19] "International" rules are as described above, with the stalemated player winning even if that player still has pieces on the board. FICS rules resolve stalemate as a win for the player with the fewer number of pieces remaining; if both have the same number, it is a draw (the piece types are irrelevant). "Joint" FICS/International rules resolves stalemate as a draw unless it is a victory for the same player under both rulesets.[13] The stalemate in the diagram is a win for White under "International" rules, a win for Black under FICS rules, and a draw under "joint" rules.
Pritchard discusses the following variants of the game inThe Encyclopedia of Chess Variants.[20]
Variant 2
Rules are the same as the main rules, except:
Variant 3
Rules are the same as the main rules, except:
Variant 4
Rules are the same as variant 3, except:
Bibliography