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Stalemate is a situation in chess where the player whose turn it is to move is not in check and has no legal move. Stalemate results in a draw. During the endgame, stalemate is a resource that can enable the player with the inferior position to draw the game rather than lose. [2] In more complex positions, stalemate is much rarer, usually taking the form of a swindle that succeeds only if the superior side is inattentive.[ citation needed ] Stalemate is also a common theme in endgame studies and other chess problems.
The outcome of a stalemate was standardized as a draw in the 19th century (). Before this standardization, its treatment varied widely, including being deemed a win for the stalemating player, a half-win for that player, or a loss for that player; not being permitted; and resulting in the stalemated player missing a turn. Stalemate rules vary in variants and other games of the chess family.
The first recorded use of stalemate is from 1765. It is a compounding of Middle English stale and mate (meaning checkmate). Stale is probably derived from Anglo-French estale meaning "standstill", a cognate of "stand" and "stall", both ultimately derived from the Proto-Indo-European root *sta-. The first recorded use in a figurative sense is in 1885. [3] [4]
Stalemate has become a widely used metaphor for other situations where there is a conflict or contest between two parties, such as war or political negotiations, and neither side is able to achieve victory, resulting in what is also called an impasse, a deadlock, or a Mexican standoff. Chess writers note that this usage is a misnomer because, unlike in chess, the situation is often a temporary one that is ultimately resolved, even if it seems currently intractable. [5] [6] [7] [8] The term "stalemate" is sometimes used incorrectly as a generic term for a draw in chess. While draws are common, they are rarely the direct result of stalemate. [9]
Diagram 1
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Diagram 4
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With Black to move, Black is stalemated in diagrams 1 to 5. Stalemate is an important factor in the endgame – the endgame setup in diagram 1, for example, quite frequently is relevant in play (see King and pawn versus king endgame). The position in diagram 1 occurred in an 1898 game between Amos Burn and Harry Pillsbury [10] and also in a 1925 game between Savielly Tartakower and Richard Réti. [11] The same position, except shifted to the e- file , occurred in a 2009 game between Gata Kamsky and Vladimir Kramnik. [12]
The position in diagram 3 is an example of a pawn drawing against a queen. Stalemates of this sort can often save a player from losing an apparently hopeless position (see Queen versus pawn endgame).
The position in diagram 5 is a special kind of stalemate, in which no move is possible even if one ignores the need to avoid self-check. George P. Jelliss has called this type of stalemate a deadlock. Adding a White knight on f2 would produce a checklock: a checkmate position where no moves are possible, even if one ignores the need to avoid self-check. In general, positions with no moves at all available (even ignoring the need to avoid self-check) are called locks. [13]
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In this position from the game Viswanathan Anand–Vladimir Kramnik from the 2007 World Chess Championship, [14] Black played 65...Kxf5, stalemating White. [15] (Any other move by Black loses.)
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An intentional stalemate occurred on the 124th move of the fifth game of the 1978 World Championship match between Viktor Korchnoi and Anatoly Karpov. [16] The game had been a theoretical draw for many moves. [17] [18] White's bishop is useless; it cannot defend the queening square at a8 nor attack the black pawn on the light a4-square. If the white king heads towards the black pawn, the black king can move towards a8 and set up a fortress.
The players were not on speaking terms, however, so neither would offer a draw by agreement. On his 124th move, White played 124.Bg7, delivering stalemate. Korchnoi said that it gave him pleasure to stalemate Karpov and that it was slightly humiliating. [19] Until 2021, this was the longest game played in a World Chess Championship final match, as well as the only World Championship game to end in stalemate before 2007. [20]
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Sometimes, a surprise stalemate saves a game. In the game Ossip Bernstein–Vasily Smyslov [21] (first diagram), Black can win by sacrificing the f-pawn and using the king to support the b-pawn. However, Smyslov thought it was good to advance the b-pawn because he could win the white rook with a skewer if it captured the pawn. Play went:
Now 60...Rh2+ 61.Kf3! Rxb2 would be stalemate (second diagram). Smyslov played 60...Kg4, and the game was drawn after 61.Kf1 (see Rook and pawn versus rook endgame). [22]
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Whereas the possibility of stalemate arose in the Bernstein–Smyslov game because of a blunder, it can also arise without one, as in the game Milan Matulović–Nikolay Minev (first diagram). Play continued:
The only meaningful attempt to make progress. Now all moves by Black (like 3...Ra3+?) lose, with one exception.
Now 4.Rxa6 would be stalemate. White played 4.Rc5+ instead, and the game was drawn several moves later. [23]
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In the game Elijah Williams–Daniel Harrwitz [24] (first diagram), Black was up a knight and a pawn in an endgame. This would normally be a decisive material advantage, but Black could find no way to make progress because of various stalemate resources available to White. The game continued:
Avoiding the threatened 73...Nc2+.
76...Nc2+ 77.Rxc2+! Kxc2 is stalemate.
77...Kxc3 is stalemate.
79...Rd3 80.Rxd3+! leaves Black with either insufficient material to win after 80...Nxd3 81.Kxa2 or a standard fortress in a corner draw after 80...Kxd3.
Now the players agreed to a draw, since 84...Kxb3 or 84...Rxb3 is stalemate, as is 84...Ra8 85.Rxc3+! Kxc3.
Black could still have won the game until his critical mistake on move 82. Instead of 82...Nc3, 82...Nb4 wins; for example, after 83.Rc8 Re3 84.Rb8+ Kc5 85.Rc8+ Kd5 86.Rd8+ Kc6 87.Ra8 Re1+ 88.Kb2 Kc5 89.Kc3 a1=Q+, Black wins.[ citation needed ]
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This 2007 game, Magnus Carlsen–Loek van Wely, ended in stalemate. [25] White used the second-rank defense in a rook and bishop versus rook endgame for 46 moves. The fifty-move rule was about to come into effect, under which White could claim a draw. The game ended:
White was stalemated. [26]
Although stalemate usually occurs in the endgame, it can also occur with more pieces on the board. Outside of relatively simple endgame positions, such as those above, stalemate occurs rarely, usually when the side with the superior position has overlooked the possibility of stalemate. [27] This is typically realized by the inferior side's sacrifice of one or more pieces in order to force stalemate. A piece that is offered as a sacrifice to bring about stalemate is sometimes called a desperado .
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One of the best-known examples of the desperado is the game Larry Evans–Samuel Reshevsky [28] that was dubbed "The Swindle of the Century". [29] Evans sacrificed his queen on move 49 and offered his rook on move 50. White's rook has been called the eternal rook. Capturing it results in stalemate, but otherwise it stays on the seventh rank and checks Black's king ad infinitum (i.e. perpetual check). The game would inevitably end in a draw by agreement, by threefold repetition, or by an eventual claim under the fifty-move rule. [30]
After 48...Qg6! 49.Rf8 Qe6! 50.Rh8+ Kg6, Black remains a piece ahead after 51.Qxe6 Nxe6, or forces mate after 51.gxf4 Re1+ and 52...Qa2+. [31]
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The position at right occurred in Boris Gelfand–Vladimir Kramnik, 1994 FIDE Candidates match, game 6, in Sanghi Nagar, India. [32] Kramnik, down two pawns and on the defensive, would be very happy with a draw. Gelfand has just played 67. Re4–e7? (first diagram), a strong-looking move that threatens 68.Qxf6, winning a third pawn, or 68.Rc7, further constricting Black. Black responded 67... Qc1! If White takes Black's undefended rook with 68.Qxd8, Black's desperado queen forces the draw with 68...Qh1+ 69.Kg3 Qh2+!, compelling 70.Kxh2 stalemate (second diagram). If White avoids the stalemate with 68.Rxg7+ Kxg7 69.Qxd8, Black draws by perpetual check with 69...Qh1+ 70.Kg3 Qg1+ 71.Kf4 Qc1+! 72.Ke4 Qc6+! 73.Kd3!? (73.d5 Qc4+; 73.Qd5 Qc2+) Qxf3+! 74.Kd2 Qg2+! 75.Kc3 Qc6+ 76.Kb4 Qb5+ 77.Ka3 Qd3+. Gelfand played 68. d5 instead but still only drew.
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In Troitsky–Vogt[ clarification needed : full name], 1896, the famous endgame study composer Alexey Troitsky pulled off an elegant swindle in actual play. After Troitsky's 1. Rd1!, Black fell into the trap with the seemingly crushing 1... Bh3?, threatening 2...Qg2#. The game concluded 2. Rxd8+ Kxd8 3. Qd1+! Qxd1 stalemate. White's bishop, knight, and f-pawn are all pinned and unable to move. [33]
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Stalemate is a frequent theme in endgame studies [34] and other chess compositions. An example is the "White to Play and Draw" study at right, composed by the American master Frederick Rhine [35] and published in 2006. [36] White saves a draw with 1. Ne5+! Black wins after 1.Nb4+? Kb5! or 1.Qe8+? Bxe8 2.Ne5+ Kb5! 3.Rxb2+ Nb3. 1... Bxe5 After 1...Kb5? 2.Rxb2+ Nb3 3.Rxc4! Qxe3 (best; 3...Qb8+ 4.Kd7 Qxh8 5.Rxb3+ forces checkmate) 4.Rxb3+! Qxb3 5.Qh1! Bf5+ 6.Kd8!, White is winning. 2. Qe8+! 2.Qxe5? Qb7+ 3.Kd8 Qd7#. 2... Bxe8 3. Rh6+ Bd6 3...Kb5 4.Rxb6+ Kxb6 5.Nxc4+ also leads to a drawn endgame. Not 5.Rxb2+? Bxb2 6.Nc4+ Kb5 7.Nxb2 Bh5! trapping White's knight. 4. Rxd6+! Kxd6 5. Nxc4+! Nxc4 6. Rxb6+ Nxb6+ Moving the king is actually a better try, but the resulting endgame of two knights and a bishop against a rook is a well-established theoretical draw. [37] [38] [39] [40] 7. Kd8! (rightmost diagram) Black is three pieces ahead, but if White is allowed to take the bishop, the two knights are insufficient to force checkmate. The only way to save the bishop is to move it, resulting in stalemate. A similar idea occasionally enables the inferior side to save a draw in the ending of bishop, knight, and king versus lone king.
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At right is a composition by A. J. Roycroft which was published in the British Chess Magazine in 1957. White draws with 1. c7! after which there are two main lines:
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Some chess problems require "White to move and stalemate Black in n moves" (rather than the more common "White to move and checkmate Black in n moves"). Problemists have also tried to construct the shortest possible game ending in stalemate. Sam Loyd devised one just ten moves long: 1.e3 a5 2.Qh5 Ra6 3.Qxa5 h5 4.Qxc7 Rah6 5.h4 f6 6.Qxd7+ Kf7 7.Qxb7 Qd3 8.Qxb8 Qh7 9.Qxc8 Kg6 10.Qe6 (first diagram). A similar stalemate is reached after: 1.d4 c5 2.dxc5 f6 3.Qxd7+ Kf7 4.Qxd8 Bf5 5.Qxb8 h5 6.Qxa8 Rh6 7.Qxb7 a6 8.Qxa6 Bh7 9.h4 Kg6 10.Qe6 (Frederick Rhine).
Loyd also demonstrated that stalemate can occur with all the pieces on the board: 1.d4 d6 2.Qd2 e5 3.a4 e4 4.Qf4 f5 5.h3 Be7 6.Qh2 Be6 7.Ra3 c5 8.Rg3 Qa5+ 9.Nd2 Bh4 10.f3 Bb3 11.d5 e3 12.c4 f4 (second diagram). Games such as this are occasionally played in tournaments as a pre-arranged draw. [42]
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There are chess compositions featuring double stalemate. To the right are two double stalemate positions, in which neither side has a legal move. An example from actual play is given below: [43]
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White played 1. Ngxf6+ Qxf6+ (if 1...exf6 then 2.Ne7#) 2. Nxf6+ exf6 3. c4 c5 4. a4 a5, leaving a double stalemate position. 1.Ndxf6+ would not have worked, for then 1...exf6 is possible. [43] (Under the present rules, the game would have ended after 1...Qxf6+, as the position is then dead: no sequence of legal moves leads to either side being checkmated.)
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The fastest known game ending in a double stalemate position was discovered by Enzo Minerva and published in the Italian newspaper l'Unità on 14 August 2007: 1.c4 d5 2.Qb3 Bh3 3.gxh3 f5 4.Qxb7 Kf7 5.Qxa7 Kg6 6.f3 c5 7.Qxe7 Rxa2 8.Kf2 Rxb2 9.Qxg7+ Kh5 10.Qxg8 Rxb1 11.Rxb1 Kh4 12.Qxh8 h5 13.Qh6 Bxh6 14.Rxb8 Be3+ 15.dxe3 Qxb8 16.Kg2 Qf4 17.exf4 d4 18.Be3 dxe3. [45]
The stalemate rule has had a convoluted history. [46] Although stalemate is universally recognized as a draw today, that was not the case for much of the game's history. In the forerunners to modern chess, such as chaturanga, delivering stalemate resulted in a loss. [47] This was changed in shatranj, however, where stalemating was a win. This practice persisted in chess as played in early 15th-century Spain. [48] Lucena (c. 1497), however, treated stalemate as an inferior form of victory; [49] it won only half the stake in games played for money, and this continued to be the case in Spain as late as 1600. [50] From about 1600 to 1800, the rule in England was that stalemate was a loss for the player administering it, a rule that the eminent chess historian H. J. R. Murray believes may have been adopted from Russian chess. [51] That rule disappeared in England before 1820, being replaced by the French and Italian rule that a stalemate was a drawn game. [52]
Throughout history, a stalemate has at various times been:
Periodically, writers have argued that stalemate should again be made a win for the side causing the stalemate, on the grounds that the goal of chess is conceptually to capture the king and checkmate merely ends it when this is inevitable. [13] Grandmaster Larry Kaufman writes, "In my view, calling stalemate a draw is totally illogical, since it represents the ultimate zugzwang, where any move would get your king taken". [76] The British master T. H. Tylor argued in a 1940 article in the British Chess Magazine that the present rule, treating stalemate as a draw, "is without historical foundation and irrational, and primarily responsible for a vast percentage of draws, and hence should be abolished". [77] Years later, Fred Reinfeld wrote, "When Tylor wrote his attack on the stalemate rule, he released about his unhappy head a swarm of peevish maledictions that are still buzzing." [78] Larry Evans calls the proposal to make stalemate a win for the stalemating player a "crude proposal that ... would radically alter centuries of tradition and make chess boring". [79] This rule change would cause a greater emphasis on material ; an extra pawn would be a greater advantage than it is today.
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However, Kaufman tested the idea of scoring stalemates higher than draws with the chess engine Komodo, and found that the impact is quite small because it is rare to be able to force stalemate but not checkmate: while all king and pawn versus king endgames become wins when the pawn is protected (except when the attacking king is trapped in front of its own rook pawn), this does not turn out to be common enough. The problem is that king and lone minor piece against king cannot force stalemate in general. Emanuel Lasker and Richard Réti proposed that both stalemate and king and minor versus king (with the minor piece side to move) should give ¾ points to the superior side: this would effectively restore not only the old stalemate rule but also the old bare king rule. Kaufman and correspondence grandmaster Arno Nickel have proposed going even further, and giving only ¼ point as well to the side that brings about a threefold repetition (which likewise has precedents in xiangqi, shogi, and Go). According to his tests with Komodo, chess at the level of a human World Championship match would have a draw rate of 65.6%; scoring stalemate as ¾–¼ reduces the draw rate to 63.4%; scoring stalemate and bare king as ¾–¼ brings it to 55.9%; and scoring stalemate, bare king, and threefold repetition as ¾–¼ brings it all the way down to 22.6%. (The same reduction of draws would occur if stalemate, bare king, and threefold repetition were scored as 1–0 instead of ¾–¼, but the point of the ¾–¼ scoring is to allow the weaker side to still benefit from avoiding checkmate, while giving the stronger side something to play for even when checkmate cannot be attained.) [80]
Jelliss has suggested that under the logic that stalemate should be a win (since any move would get the king taken), checklock should be a draw. (In a checklock position, no forward play is possible even if exposing the king to check is valid, so the king cannot get captured. The same logic would apply to deadlock.) [13]
If stalemate were a loss for the player unable to move, the outcome of some endgames would be affected. [33] In some situations the superior side can force stalemate but not checkmate. In others, the defending player can use stalemate as a defensive technique to avoid losing (under the current rule):
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The effect if stalemates were to be scored as ¾–¼ would be similar but less severe, as then the weaker side would still be rewarded somewhat for avoiding checkmate via stalemate, just not as much as before. [80]
Not all variants of chess consider the stalemate to be a draw. Many regional variants, as well some variants of Western chess, have adopted their own rules on how to treat the stalemated player. In chaturanga, which is widely considered to be the common ancestor of all variants of chess, a stalemate was a win for the stalemated player. [82] [83] Around the 7th century, this game was adopted in the Middle East as shatranj with very similar rules to its predecessor; however, the stalemate rule was changed to its exact opposite: i.e. it was a win for the player delivering the stalemate. [84] This game was in turn introduced to the Western world, where it would eventually evolve to modern-day Western chess, although the stalemate rule for Western chess was not standardized as a draw until the 19th century (see history of the rule).
Chaturanga also evolved into several other games in various regions of Asia, all of which have varying rules on stalemating:
The majority of variants of Western chess do not specify any alterations to the rule of stalemate. There are some variants, however, where the rule is specified to differ from that of standard chess:
There is a world of difference between no choice ... and a poor choice. Editorial writers often talk about a political stalemate when the analogy they probably have in mind is a political "zugzwang". In stalemate a player has no legal moves, period. In zugzwang he has nothing pleasant to do.
The bishop is a piece in the game of chess. It moves and captures along diagonals without jumping over interfering pieces. Each player begins the game with two bishops. The starting squares are c1 and f1 for White's bishops, and c8 and f8 for Black's bishops.
The endgame is the final stage of a chess game which occurs after the middlegame. It begins when few pieces are left on the board.
In the game of chess, perpetual check is a situation in which one player can play an unending series of checks, from which the defending player cannot escape. This typically arises when the player who is checking feels their position in the game is inferior, they cannot deliver checkmate, and wish to force a draw.
The fifty-move rule in chess states that a player can claim a draw if no capture has been made and no pawn has been moved in the last fifty moves. The purpose of this rule is to prevent a player with no chance of winning from obstinately continuing to play indefinitely or seeking to win by tiring the opponent.
Checkmate is any game position in chess and other chess-like games in which a player's king is in check and there is no possible escape. Checkmating the opponent wins the game.
The two knights endgame is a chess endgame with a king and two knights versus a king. In contrast to a king and two bishops, or a bishop and a knight, a king and two knights cannot force checkmate against a lone king. Although there are checkmate positions, a king and two knights cannot force them against proper, relatively easy defense.
The Saavedra position is one of the best-known chess endgame studies. It is named after the Spanish priest Fernando Saavedra (1849–1922), who lived in Glasgow during the late 19th century. Though not a strong player, he spotted a win involving a dramatic underpromotion in a position previously thought to have been a draw.
In chess, promotion is the replacement of a pawn with a new piece when the pawn is moved to its last rank. The player replaces the pawn immediately with a queen, rook, bishop, or knight of the same color. The new piece does not have to be a previously captured piece. Promotion is mandatory when moving to the last rank; the pawn cannot remain as a pawn.
The Tarrasch rule is a general principle that applies in the majority of chess middlegames and endgames. Siegbert Tarrasch (1862–1934) stated the "rule" that rooks should be placed behind passed pawns – either the player's or the opponent's. The idea behind the guideline is that (1) if a player's rook is behind their own passed pawn, the rook protects it as it advances, and (2) if it is behind an opponent's passed pawn, the pawn cannot advance unless it is protected along its way.
The chess endgame with a king and a pawn versus a king is one of the most important and fundamental endgames, other than the basic checkmates. It is an important endgame for chess players to master, since most other endgames have the potential of reducing to this type of endgame via exchanges of pieces. Players need to be able to determine quickly whether a given position is a win or a draw, and to know the technique for playing it. The crux of this endgame is whether or not the pawn can be promoted, so checkmate can be forced.
In chess, the exchange is the material difference of a rook for a minor piece. Having a rook for a minor piece is generally advantageous, since the rook is usually more valuable. A player who has a rook for a minor piece is said to be up the exchange, and the other player is down the exchange. A player who wins a rook for a minor piece is said to have won the exchange, while the other player has lost the exchange. The opposing captures often happen on consecutive moves, but this is not strictly necessary. Although it is generally detrimental to lose the exchange, one may occasionally find reason to purposely do so; the result is an exchange sacrifice.
In chess, a fortress is an endgame drawing technique in which the side behind in material sets up a zone of protection that the opponent cannot penetrate. This might involve keeping the enemy king out of one's position, or a safe zone the enemy cannot force one out of. An elementary fortress is a theoretically drawn position with reduced material in which a passive defense will maintain the draw.
The rook and pawn versus rook endgame is a fundamentally important, widely studied chess endgame. Precise play is usually required in these positions. With optimal play, some complicated wins require sixty moves to either checkmate, capture the defending rook, or successfully promote the pawn. In some cases, thirty-five moves are required to advance the pawn once.
In chess, a blunder is a critically bad mistake that severely worsens the player's position by allowing a loss of material, checkmate, or anything similar. It is usually caused by some tactical oversight, whether due to time trouble, overconfidence, or carelessness. Although blunders are most common in beginner games, all human players make them, even at the world championship level. Creating opportunities for the opponent to blunder is an important skill in over-the-board chess.
The chess endgame of a queen versus pawn is usually an easy win for the side with the queen. However, if the pawn has advanced to its seventh rank it has possibilities of reaching a draw, and there are some drawn positions with the pawn on the sixth rank. This endgame arises most often from a race of pawns to promote.
In chess, a swindle is a ruse by which a player in a losing position tricks their opponent and thereby achieves a win or draw instead of the expected loss. It may also refer more generally to obtaining a win or draw from a clearly losing position. I. A. Horowitz and Fred Reinfeld distinguish among "traps", "pitfalls", and "swindles". In their terminology, a "trap" refers to a situation where players go wrong through their own efforts. In a "pitfall", the beneficiary of the pitfall plays an active role, creating a situation where a plausible move by the opponent will turn out badly. A "swindle" is a pitfall adopted by a player who has a clearly lost game. Horowitz and Reinfeld observe that swindles, "though ignored in virtually all chess books", "play an enormously important role in over-the-board chess, and decide the fate of countless games".
The opposite-colored bishops endgame is a chess endgame in which each side has a single bishop and those bishops operate on opposite-colored squares. Without other pieces besides pawns and the kings, these endings are widely known for their tendency to result in a draw. These are the most difficult endings in which to convert a small material advantage to a win. With additional pieces, the stronger side has more chances to win, but still not as many as when bishops are on the same color.
A pawnless chess endgame is a chess endgame in which only a few pieces remain, and no pawns. The basic checkmates are types of pawnless endgames. Endgames without pawns do not occur very often in practice except for the basic checkmates of king and queen versus king, king and rook versus king, and queen versus rook. Other cases that occur occasionally are (1) a rook and minor piece versus a rook and (2) a rook versus a minor piece, especially if the minor piece is a bishop.
The rook and bishop versus rook endgame is a chess endgame where one player has just a king, a rook, and a bishop, and the other player has just a king and a rook. This combination of material is one of the most common pawnless chess endgames. It is generally a theoretical draw, but the rook and bishop have good winning chances in practice because the defense is difficult. Ulf Andersson won the position twice within a year, once against a grandmaster and once against a candidate master; and grandmaster Keith Arkell has won it 27 times out of 27. In positions that have a forced win, up to 59 moves are required. Tony Kosten has seen the endgame many times in master games, with the stronger side almost always winning. Pal Benko called this the "headache ending." David Howell observed, "Especially below elite grandmaster level, this is one of the hardest endgames to draw."
In a chess endgame of a king, bishop, and pawn versus king, a wrong rook pawn is a rook pawn whose promotion square is the opposite color from the bishop's square color. Since a side's rook pawns promote on opposite-colored squares, one of them may be the "wrong rook pawn". This situation is also known as having the wrong-colored bishop or wrong bishop. In many cases, the wrong rook pawn will only draw, when any other pawn would win. This is because the defending side can sometimes get their king to the corner in front of the pawn, after which the attacking side cannot chase the king away to enable promotion. A fairly common defensive tactic is to reach one of these drawn endgames, often through a sacrifice.