Jan Rusinek (born 2 December 1950) is a Polish mathematician and chess composer, particularly noted for his brilliant endgame studies.
He was editor of the study section of Szachy (Chess) from 1971 to the magazine's closure in 1990. Rusinek became an International Judge of chess composition in 1983, and a Grandmaster of chess composition in 1992. He won over 30 first prizes in composing tourneys. The Oxford Companion to Chess opines that "his achievements are likely to rival those of his greatest predecessors".
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To the left is one of Rusinek's better known studies. Black threatens Nb5-d6# or Ne4-d6# and 1.Kb7 Bd5+ does not help, so 1.a7 is necessary. Now 1...Bd5 can be answered with, among other lines, 2.g8Q Bxg8 3.a8Q Nxb6+ 4.Kb7 Nxa8 5.Kxa8 Be6 6.Kb8 and Black must give up a piece for the c pawn, so instead 1...Ba6+ 2.b7. Now 2...Nb5 threatens 3...Nd6# but is met with 3.g8N+ Ke8 4.Nf6+ when 4...Nxf6 loses to 5.a8Q. Instead, therefore, Black plays 2...Ne4 3.g8N+! Ke8 4.Nf6+ and now 4...Nexf6 is possible. This seems to put White in a dilemma, since 5.a8Q loses to 5...Nd5 with 6...Ne7# next move. But instead there is 5.a8B!! when 5...Nd5 is stalemate, so therefore 5...Ne5 6.Kb8 Nc6+ 7.Kc8 Bf1 and again White has a problem because 8.b8Q will lose to 8...Ba6+ 9.Qb7 Ne4 10.Qxa6 Nd6#. 8.b8N is no better: 8...Ne7+ 9.Kb7 Bg2+ 10.Ka7 (10.Nc6 Bxc6+ 11.Ka7 Bd7) 10...Nc8+ 11.Ka6 Bxa8. However, white can draw with a third underpromotion: 8.b8R!!. Now after 8...Ba6+ 9.Rb7, 9...Ne4 is stalemate, and there is no useful way for Black to avoid this. White draws.
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White's being required to make all three underpromotions in order to draw is exceptionally unusual. In Endgame Magic (Batsford, 1996), John Beasley and Timothy Whitworth comment that it "represents a very much greater feat of composition than might at first appear. That it was accomplished with the use of only nine men adds still more to the composer's achievement." Beasley and Whitworth also comment that "It is quite easy to construct a position in which White must promote to a rook or bishop in order to avoid giving stalemate," but "It is much more difficult to create a position in which White must underpromote to create a stalemate," which is done on two occasions in this study.
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Rusinek subsequently (64, 27 July 1978) added an introduction to this study which added a promotion to queen to the already existing underpromotions, thus creating an Allumwandlung. This later version is shown to the right. 1.h8R+ is insufficient, since 1...Ke7 will mate quickly. 1.h8Q+ is therefore necessary, and after the forced continuation 1...Qxh8 2.g7+ Qxg7 3.hxg7+ Ke7, the initial position of the original study is reached. Rusinek himself considered this version inferior to the original (aesthetics versus task).
In the game of chess, an endgame study, or just study, is a composed position—that is, one that has been made up rather than played in an actual game—presented as a sort of puzzle, in which the aim of the solver is to find the essentially unique way for one side to win or draw, as stipulated, against any moves the other side plays. If the study does not end in a mate or stalemate, it should be obvious that the game is either won or drawn, and White can have a selection of many different moves. There is no limit to the number of moves which are allowed to achieve the win; this distinguishes studies from the genre of direct mate problems. Such problems also differ qualitatively from the very common genre of tactical puzzles based around the middlegame, often based on an actual game, where a decisive tactic must be found.
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.
In chess, promotion is the replacement of a pawn with a new queen, rook, bishop, or knight of the same color. It occurs immediately when the pawn moves to its last rank, with the player choosing the piece of promotion. The new piece does not have to be a previously captured piece. Promotion is mandatory; the pawn cannot remain as a pawn.
In chess, a grotesque is a problem or endgame study which features a particularly unlikely or impossible initial position, especially one in which White fights with a very small force against a much larger black army. Grotesques are generally intended to be humorous.
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 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 bishop and knight checkmate in chess is the checkmate of a lone king which can be forced by a king, a bishop, and a knight. With the stronger side to move and with perfect play, checkmate can be forced in at most thirty-three moves from any starting position where the defender cannot quickly win one of the pieces. The exception is the "stalemate trap". These exceptions constitute about 0.5% of the positions. Checkmates are possible with the defending king on any square at the edge of the board but can be forced only from positions with different material or if the defending king is in a corner controlled by the bishop or on a square on the edge next to a corner; however, mate adjacent to the corners not controlled by the bishop is only two moves deep, so it is not generally encountered unless the defending side plays inaccurately. Although this is classified as one of the four basic or elementary checkmates, it occurs in practice only approximately once in every 6,000 games.
Edmar John Mednis was a Latvian-American chess player and writer of Latvian origin. He was awarded the title of Grandmaster by FIDE in 1980.
In chess, a desperado piece is a piece that is either en prise or trapped, but captures an enemy piece before it is itself captured, or is used as a sacrifice that will result in stalemate if it is captured. The former case can arise in a situation where both sides have hanging pieces, in which case these pieces are used to win material prior to being captured. A desperado in the latter case is usually a rook or a queen; such a piece is sometimes also called crazy or mad.
Leopold Adamovich Mitrofanov was a Russian chess composer, an International Judge of Chess Composition and an International Master of Chess Composition. He was born in Leningrad and, by profession, was a chemical engineer.
In chess, a swindle is a ruse by which players in a losing position trick their opponent and thereby achieve 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 World Chess Championship 2010 match pitted the defending world champion, Viswanathan Anand, against challenger Veselin Topalov, for the title of World Chess Champion. The match took place in Sofia, Bulgaria from 24 April to 13 May 2010, with a prize fund of 2 million euros. Anand won the final game to win the match 6½–5½ and retain the title.
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Chess on a really big board is a large chess variant invented by Ralph Betza around 1996. It is played on a 16×16 chessboard with 16 pieces and 16 pawns per player. Since such a board can be constructed by pushing together four standard 8×8 boards, Betza also gave this variant the alternative names of four-board chess or chess on four boards.
The Berlin Defence, also called the Berlin Wall, is a chess opening that begins with the moves:
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