Thursday, June 26, 2008

Solving contest 1984-02-05, Patras

We present here the problems of an old solving contest. This event was held 05-Feb-1984 at the "S.O.Patron, Chess Club of Patras" with problem selection by Mr Manolas Emmanuel.
The winners, who had solved all the problems, were the following :
(1) Pountzas Chrysanthos, 53 minutes,
(2) Gerogiannis Christodoulos, 1 hour and 9 minutes
(3) Skoularikis Fotios, 1 hour and 17 minutes.

Try to solve the problems without seeing the analytical explanations in the end of this post. If your time is under one hour and a half, then you may consider yourself as very good solver.

 (Problem 100) N. Kossolapov “Novosty”, 1963 Mate in 2, #2 (6+1) [2K4Q/8/2S5/1k6/3B4/8/P5P1/8]

 (Problem 101) M. Lipton, Second Honorary Mention, “Israel Problemists’ Assn. Tourney”, 1955 (There is set play). Mate in 3, * #3 (4+3) [k1K5/1p2R3/q7/3B4/8/4B3/8/8]

 (Problem 102) H. Lepuschütz, “Deutsche Schachzeitung“, 1936 Mate in 6, #6 (6+15) [2r5/P2R4/K6R/Spk3pp/p2p1p1r/P2p4/1p5b/3bs2s]

 (Problem 103) H. Mattison, First-Second Prize, “Schachmatny Listok”, 1929 White plays and wins, + (4+4) [8/6k1/1PPR4/2r5/7p/7b/3K4/8]

 (Problem 104) E. A. Wirtanen, First Prize, “Leipzig Olympic Tourney”, 1960 (There is set play). Selfmate in 2, * s#2 (11+8) [4S3/3p2S1/1p1P1pP1/1R1bk1Pp/7p/3BK2Q/1r3P2/B7]

 (Problem 105) L. I. Loshinski, First Prize, “Problem”, 1973 Helpmate in 5, h#5 (2+14) [b7/pk4q1/pp1s2r1/1r3p1K/4p3/3p1s1B/4p3/8]

Solutions of the problems

Problem-100, Kossolapov, #2
Phases of virtual play : Tries : {1.Qe5+? / Qh5+? / Qd8? Kc4!}, {1.Qg8? Kxc6!}, {1.Qf8?, if 1...Ka4 / Ka6 / Kc6 then 2.Qb4 / Qf1 / Qc5, but 1...Kc4!}.
Phase of actual play : Key : 1.Qh3!
1...Ka4 / Ka6 / Kc6 / Kc4 2.Qb3 / Qd3 / Qd7 / Qb3

Theme X-flights of bK. Three changed mates.

Problem-101, Lipton, * #3
Phase of set play : (*) 1...Qc4 / Qe6 / Qc6 2.BxQ (grabbing).
Phases of virtual play : Tries : {1.Re4? Qc4!}, {1.Re8?, if 1...Qc4 / Qe6 2 Kd7 / Kc7, but 1...Qb6!} (royal battery).
Phase of actual play : Key : 1.Rb7! Qc4 / Qe6 / Qc6 2.Rc7 / Rd7 / Rc7

The composer presents here the theme Brede in a Zagoruiko frame.

 Theme Brede cross-checks : Every black check is answered with white check that pins the white piece, which then is unpinned and delivers mate.

Problem-102, Lepuschütz, #6
Phases of virtual play : Tries : {1.Rd5+ Kxd5!}, {1.a8=Q/R? Rxa8+!}, {1.Rc6+? Rxc6+!}, {1.Sb7+? Kc4!}, {1.Rb6? b1=Q/R!}, {1.Rd6? Bf3!}, {1.Re6? f3!}, {1.Rf6? Bg4!}.
Phase of actual play : Key : 1.Rg6! Rg4
2.Rf6 Sg3
3.Re6 Sf3
4.Rd6 Bb3
5.Rb6 Rb8
6.Rc6#

Problem-103, Mattison, +
Key : 1.b7! Rb5
2.Rd8 Bg2
3.b8=Q Rb8
4.c7! Rb2
5.Kc1! Rb6
6.Rg8 Kh6
7.Rg2 Rc6
8.Rc2 (+–)

Problem-104, Wirtanen, * s#2
Phase of set play : (*)
1...f5 2.f3 f4#
1...g5 2.f4 gxf4#
Phase of actual play : Key : 1.Qh4!
1...f5 2.Qh5 f4#
1...g5 2.Qf4 gxf4#

We see two changed mates here.

Problem-105, Loshinski, h#5
Obviously the mate is given by the wB. Where can the bK be cornered?
Key : 1.a5! Bg4
2.Ka6 Bf5
3.Bd5 Be6
4.Sf5 Bd7
5.Bf7 Bc8#

(This post in Greek language).

Tuesday, June 24, 2008

Nightrider

The Nightrider, (German Nachtreiter, French Noctambule), is a fairy piece, which has been invented in 1925 by the British founder of the fairy chess T. R. Dawson.

The Nightrider moves in a straight line with one or more Knight-steps. It is a (1,2)Rider and it is symbolized in chess diagrams with an upside-down Knight 'looking' to the right and in texts with the letter N.
Since the Nightrider is a linear piece, we can observe mutual interferences between Nightriders and other linear pieces.
If there is an opponent piece on the arrival square, the Nightrider captures it. All the intermediate steps must be on free squares. If the Nightrider stands on a8, it can move to b6, c4, d2, c7, e6, g5. If we put on b6 a piece, if it is friendly piece the nightrider can not move to b6, if it is opponent piece it can be captured, and in both cases the nightrider cannot move to c4 και d2.

If there are Nightriders in the initial problem position, then a pawn can be promoted to Nightrider.

The Knight, depending on where it stands on the chessboard can threaten 2, 3, 4, 6, 8 squares. The Nightrider, on the other hand, can threaten 6, 7, 8, 9, 10, 11, 12 squares.

 (Problem 107) T. R. Dawson, British Chess Magazine, 1925 Mate in 5, (Nightrider on c6) #5 (3+1) (1+0 nightrider) [8/2K5/k1Ν5/8/8/2S5/8/8]

The King together with two Knights cannot win a King (K + S + S vs K), but the King together with a Knight and a Nightrider (K + S + N vs K) can win a King! (Because the Knight cannot win a tempo, but the Nightrider can!).

Tries: {1.Kc8? / Kb8? Kb6!}, {1.Ne2? / Ng4? / Ne5? Ka5!}, {1.Ng8? Ka7!}, {1.Sc3~? K(x)b5!}.
Key 1.Ne7! Ka7
2.Ng3 Ka8 3.Ne4 Ka7 4.Sb5+ Ka8 5.Nd2#

 (Problem 154) T. R. Dawson, Problemist, 01/1927 Mate in 2, (Nightrider on e5) #2 (6+7) (1+0 nightrider) [2s5/8/pP2p3/2KbN3/2pP4/2S5/2s5/k2S4]

In orthodox problems the royal battery has at most 6 thematic variations (task).
In problem-154 Dawson shows the royal battery, with a King and a Nightrider, to have 8 thematic variations! (Fairy task)!

Key 1.Nd7! (zz zugzwang).
1...Sc8~ 2.Kd6#
1...e5 2.Kxd5#
1...Sxd4 2.Kxd4#
1...Bd5~ 2.Kxc4#
1...Sc2~ / Sb4 2.K(x)b4 #
1...a5 2.Kb5#
1...Sxb6 2.Kxb6#
1...Bc6 2.Kxc6#

(This post in Greek language).

Sunday, June 22, 2008

Greek Terminology for problemists

(Reference post. Last Update : 05-08-2010).

Part A: Basic terminology about chess problems

Here are presented terms relevant with chess problems in Greek language, and also in English, French, and German (the three languages supported by FIDE). For anyone interested for these terms in Czech or Finnish, there is the original site of Vaclav Kotesovec. Especially for the basic pieces, see the site of Ari Luiro, who gives their names in 73 languages (or dialects!).

 Greek English German French Skaki, Zatrikio chess Schach echecs Lefkos white Weiss blanc Mavros black Schwarz noir Vassilias King Koenig Roi Vassilissa Queen Dame Dame Pyrgos Rook Turm Tour Axiomatikos Bishop Leufer Fou Hippos Knight Springer Cavalier Pioni, Stratiotis Pawn Bauer Pion Akrida Grasshopper Grashuepfer Sauterelle Kavalaris tis nihtas Nightrider Nachtreiter Noctambule Ekfonissi stipulation Forderung anonce dio lissis 2 solutions 2 Loesungen 2 solutions Iconiko pegnidi set play Satzspiel jeu apparent Phaenomeniko pegnidi set play Satzspiel jeu apparent Kinissi move Zug coup Klidi key-move Schluessel cl? Dokimi try Verfuehrung essai Apili threat Drohung menace Apoklismos zugzwang Zugzwang blocus Sah! (+) check! Schach! echec! Mat (#), Niki mate Matt mat Pat (=), issopalia stalemate Patt pat Issopalia draw Remis nulle Provlima problem Aufgabe probleme Prototypo original Urdruck inedit Mythiko skaki fairy chess Maerchenschach echecs feeriques Voithitiko helpmate Hilfsmatt mat aide Antistrofo selfmate Selbstmatt mat inverse Skakiera chess board Schach Brett echiquier Tetragono square Feld case Komati, Pessos piece Stein piece Parsimo capture Schlag prise (x,y)Altis (x,y)Leaper (x,y)Springer bondisseur(x,y) (x,y)Dromeas (x,y)Rider (x,y)Reiter . Empodistis Hopper . . Tripio cook Nebenloesung demoli Alyto unsolvable unloesbar insoluble Antissipe anticipation Vorgaenger anticipation Vravio prize Preis Prix Efimi mnia honourable mention ehrende Erwaehnung Mention d' Honneur Epenos commendation Lob Recommande

Part B: Terminology with explanations

Here are presented explanations of terms relevant to chess compositions and some links are added to posted problems. Terms with special meaning are written with bold letters.

The catalog is not complete and additions or corrections are welcomed. You may also search in other published catalogs (as is Themes by Christian Poisson).

=== === === === === === === ===
Term in English : Explanation. [Greek Term [Pronunciation of Greek term]]
=== === === === === === === ===

Actual play or After the key play :
This play is the moves following the key and satisfying the stipulation of the problem, in other words it is the phase of the actual play. Note that set play is the phase before the key, and virtual play is the phase after each try.
[Greek Πραγματικό παιγνίδι [pra-ghma-ti-ko’ pe-ghni’-di]]

Allumwandlung :
In a problem we see all the promotions to Q, R, S, B. This can happen to one ore more pawns, in one or more phases. This multiple promotion is noted with the german term Allumwandlung (AUW). There is white and black AUW. See theme Babson.
[Greek Αλουμβάντλουνγκ [al-um-va’nt-lung]]

Annihilation :
To make a piece disappear, (a piece hindering the execution of a plan), we sacrifice it or bury it. See 204.
[Greek Εξαφάνιση [ex-a-fa’-ni-si]]

Anticipated :
If the theme and the position of a problem-B have already appeared in a previous problem-A, without the composer of problem-B having knowledge of this fact, then the problem-B is declared anticipated. It is not necessary for the position to be exactly the same, it is enough to be similar. If this similarity is known to the composer of problem-B, we are talking about plagiarism. The possibility to be a problem anticipated is great if its theme is simple, since the themes are few and chess problems are being composed hundreds of years now. The judges of the contests are very experienced, but to make sure that the entries in a contest are original, computers with huge chess problem databases are also used.
[Greek Μη πρωτότυπο [mi pro-to’-ti-po]]

Anticritical move :
A piece (A) passes over a critical square and avoids to be blocked from another piece (B) that goes on this square. See here.
[Greek Αντικρίσιμη [a-nti-kri’-ssi-mi]]

Aristocratic :
A problem with no pawns in the initial position. See here.
[Greek Αριστοκρατικό [a-ri-sto-kra-ti-ko’]]

AUW (see Allumwandlung) or multiple promotion :
A problem including in its solution promotions of pawns to all kinds of pieces. In orthodox chess : promotion to Queen, Rook, Bishop, Knight.
[Greek Πολλαπλή προαγωγή [po-la-pli’ pro-a-gho-ghi’]]

Battery :
We have on the same line a white piece-B which can threaten the black King, a white piece-A which does not threaten the bK, and the bK. The pieces A and B form the Battery. If the front piece-A is lifted, the battery is firing since the discovery of piece-B gives check. For example, if a white Knight is positioned between a white Rook and the black King, any move of the white Knight discovers check from the white Rook. If the Battery aims at a square, where the King goes later in the solution, we have indirect battery. See 004 069 176.
[Greek Μπαταρία [ba-ta-ri’-a]]

Block :
It is a problem where the key does mot introduce a threat but brings black in a Zugzwang situation where every black move loses. In the Perfect block, every black move in the set play is answered with mate and the key is simply a waiter move. In the Incomplete block there are not set mates for all the black moves, thus the key prepares the needed answers. In the Mutate problem some of the mates of the set play are changed after the key in the actual play. See here.
[Greek Μπλοκ [blok]]

By-play :
This play is the variations not relevant with the theme of the problem. The other variations are called thematic variations.
[Greek Παράπλευρο παιγνίδι [pa-ra’-ple-vro pe-ghni’-di]]

Castling :
Special move of the King, where one of his Rooks takes part. (They have not previously moved, there is no threat for the King and the next two squares towards the Rook, there is no piece between them). The King makes two steps towards the Rook and the Rook goes where the King made the first step. See The Key.
[Greek Ροκέ [ro-ke’]]

Chess :
A game having great complexity.
[Greek Σκάκι [ska'-ki]]

Chess notation :
It is the special notation (i.e. algebraic, Forsythe, etc) used by chess players and problemists for writing games and positions. See here.
[Greek Σκακιστική γραφή [ska-ki-sti-ki’ ghra-fi’]]

Chess problem :
There are many types of chess problems. The composers are usually specialised in some of these types. See Types of chess problems.
[Greek Πρόβλημα σκακιστικό [pro’-vli-ma ska-ki-sti-ko’]]

Circuit, Round trip (German : Rundlauf) :
A piece departs from asquare and later in the solution returns on it after a polygonic trip (i.e. a Rook goes e3 - g3 - g5 - e5 - e3). Special cases are the King’s triangle and the Queen’s triangle. (Compare these moves to Comeback, where the trip is on straight line). See here.
[Greek Κύκλωμα [ki’-klo-ma], Ταξίδι μετ’ επιστροφής [ta-xi’-dhi met e-pi-stro-fi’s]]

Clearance :
Generally, the relocation of a piece to allow the move of another piece towards a certain square. The clearance may be a line-opening or a piece-annihilation.
[Greek Εκκένωση [e-ke’-no-si]]

Composer :
The person composing a problem. Some problems have been created by cooperation of composers. See Composers and problems.
[Greek Συνθέτης [sin-the’-tis]]

Composition of Chess problems :
Chess problems are created by composers and, in a different time, the solvers try to find the solutions. It is quite different, as a discipline, from the Over-the-Board (OTB) Chess (or Club chess) which is a game between two players. See OTB chess vs compositions.
[Greek Καλλιτεχνικό σκάκι [ka-li-teh-ni-ko’ sk’a-ki], (= artistic chess)]

Condition Anticirce :
It is a heterodox fairy condition, where capturing pieces are reborn (the captured pieces are lost). See here.
[Greek Συνθήκη Αντικίρκη [sin-thi’-ki an-ti-ki’r-ki]]

Condition Circe :
It is a heterodox fairy condition, where the captured pieces are reborn. See here and here.
[Greek Συνθήκη Κίρκη [sin-thi’-ki ki’r-ki]]

It is a heterodox fairy condition, specifying that if a piece is threatening a similar opponent piece (R with R, S with S, B with B, etc), then both pieces are paralyzed and lose all powers except the power of paralyzing the opponent. See here.
[Greek Συνθήκη Μαντράσι [sin-thi’-ki ma-dra’-si], Βασιλικό Μαντράσι [va-si-li-ko’ ma-dra’-si] ]

Condition Maximummer :
It is a heterodox fairy condition, where it is obligatory to play the piece with the longest (geometrically) move.
Condition Black Maximummer : The maximummer condition is applied only for black pieces. This type of problem is usually a selfmate problem. See here.
[Greek Συνθήκη Μαξιμούμερ [sin-thi’-ki ma-xi-mu’-mer]]

Cook :
It is another, different from the key, first move that solves the problem, which the composer had not seen. The undesired second solution is a very serious defect that ruins the problem. Some decades ago it was commonplace the publication of cooked problems, but now the problems are checked by computers (for example : programs Fancy and Popeye) and the Cooked problems are almost extinct.
[Greek Τρύπα [tri’-pa]]

Correction :
Seeing that a move has a disadvantage we make anoter move, which is called correction, to remove this disadvantage (but we might introduce another). There is white and black correction. There is primary, secondary, tertiary, quaternary correction. See here.
[Greek Διόρθωση [di-o’r-tho-si]]

Critical move :
A linear piece A moves beyond a critical square, on which a second piece B will go and it will inhibit by its presence the influence of the linear piece A. See here and 070.
[Greek Κρίσιμη κίνηση [kri’-si’mi ki’-ni-si]]

Crossed checks :
At least three checks in continuous (half-)moves White – Black - White. See 133.
[Greek Διασταυρωμένα σαχ [di-a-sta-vro-me’-na sah]]

Cyclic change :
Suppose that (A, B, C) are the mates that can be done after some (x, y) black answers. We may observe that in various phases we have cyclic (or compinatory) change of the mates : (xA, yB) and (xA, yC) and (xC, yB). See here.
[Greek Κυκλική εναλλαγή [ki-kli-ki’ e-na-la-ghi’]]

Cylinder-board :
There are three types. [Vertical cylinder : a chessboard where it is supposed that the files a and h are in contact. To the right of h8 lies a8. From h8 up there is nothing], [Horizontal cylinder : a chessboard where it is supposed that the rows 1 and 8 are in contact. From h8 up lies h1. There is nothing to the right of h8], [Anchor ring : The combination of vertical and horizontal cylinder. From h8 up lies h1. To the right of h8 lies a8. From h8 diagonally up right lies a1.].
[Greek Σκακιέρα κυλινδρική [ska-kie’-ra ki-lin-dhri-ki’]]

Delocation :
Forcing a piece to move in a place, from where it cannot take part in the defense. See 121.
[Greek Απομάκρυνση [a-po-ma’-kri-nsi]]

Direct mate :
The type of problem where white moves first and must mate in a certain number of moves, no matter what the black defenses are. Such a problem has usually the stipulation Mate in 2 moves (or in another number of moves). The term orthodox is used to discriminate the direct mates from other kinds of problems, called heterodox, for example helpmates, selfmates and fairy.
[Greek Ορθόδοξο [or-tho’-dho-xo]]

Domination :
The side with less force can exploit the position and can capture pieces of the stronger side. See here.
[Greek Κυριαρχία [ki-ri-ar-hi’a]]

Doubling :
A manoeuvre which puts two pieces in a line (row, file or diagonal) in order to support one another.
[Greek Δίπλωμα [di’-plo-ma]]

Doubling Brunner-Turton :
It is a Turton Doubling, where the two pieces are equal in strength.
[Greek Δίπλωμα Μπρούνερ-Τέρτον [di’-plo-ma bru’-ner te’r-ton]]

Doubling Loyd-Turton :
It is a Turton Doubling, where the first piece is stronger.
[Greek Δίπλωμα Λόιντ-Τέρτον [di’-plo-ma lo’-id te’r-ton]]

Doubling Turton :
See Theme Turton doubling
[Greek Δίπλωμα Τέρτον [di’-plo-ma te’r-ton]]

Doubling Zepler :
It is a kind of doubling of pieces, where one piece is moving on a line towards one direction, a second piece comes on this line, and then the first piece moves on this line towards the same initial direction. It is a three-move theme.
[Greek Δίπλωμα Τσέπλερ [di’-plo-ma tse’-pler]]

Dual :
White should have only one move in each critical point of the solution. If white has alternative possibilities for moving (excluding the first move, the key), this is called dual. It is not as serious defect as the cook, and in not thematic variations may be tolerated, but there are different opinions on this subject. See Theme Java for Dual avoidance, which is considered good.
[Greek Δυάδα [thi-a’-tha], Ντουάλ [du-a’l]]

Dual avoidance :
If, from a couple of seemingly equivalent white moves, only one is effective in each variation of the solution, we have Dual Avoidance which is an asset for the problem. The French term for the (undesirable) pair of moves is Dual.
[Greek Αντιδυάδα [a-nti-thi-a’-tha]]

Duplex :
It is a type of problem with two solutions, where in the second solution the roles of the colors are interchanged. Most common type is the Duplex helpmate, in which the two solutions have stipulations : (1) black plays first and, with help from the white, black is mated and (2) white plays first and, with help from black, white is mated. See 098 157.
[Greek Ντούπλεξ [du’-plex]]

Economy :
Economy is a plus in a chess composition, but the exact specification of the element that must be economical is a subject of discussion. We consider important all the aspects of economy : economy of material or forces, economy of space, economy of motivation, economy of moves. See Originality and Economy.
[Greek Οικονομία [i-ko-no-mi’-a]]

ELO rating :
It is an international (defined by the professor Arpad Elo) way of specifying the efficiency of a chess player.
[Greek Βαθμός ΕΛΟ [va-thmo’s e’-lo]]

En passant (from French, in the passing) :
Special movement of a Pawn-a that has already moved three steps, in which movement takes part a Pawn-b of the opponent which stands on the next file on its initial square. The Pawn-b moves with double step and goes to a square next (on the same row) to Pawn-a. The Pawn-a can capture Pawn-b in the very next move, as if Pawn-b had moved with single step. This en-passant capture is executed at once or is lost, because it cannot be postponed. See The Key and here.
[Greek Ανπασάν [an-pa-sa’n]]

Fairy chess :
In Fairy chess belong the problems which apply heterodox conditions (i.e. Circe, Madrasi, etc) or use special fairy pieces. Other examples are the Maximummer problems with moves in maximum distances, the problems on Cylinder chessboards or on Grid chessboard, the problems with Retroanalysis. See here.
[Greek Μυθικό σκάκι [mi-thi-ko’ ska’-ki]]

Flight square :
The square on which the black King can move legally (the square not threatened by a white piece and not occupied by a black piece). If black puts a piece on a flight square, limiting the mobility of the black King, the move is a self-block. If black relocates a blocking piece to create a flight, the move is square clearance.
[Greek Τετράγωνο Διαφυγής [te-tra’-go-no di-a-fi-ghis]]

Forced :
Obligatory move. See 081.
[Greek Φορσέ [for-se’]]

Gambit :
Sacrifice of a Pawn during the opening of a game. See 004.
[Greek Γκαμπί [ga-mbi’]]

Grasshopper :
Popular fairy piece, hopper type. See here.
[Greek Ακρίδα [a-kri’-tha]]

Grid-board :
A chessboard used in Fairy chess, which is divided as grid of 16 (non-overlapping) square areas each having 2x2 squares of the chessboard. Legal moves are those that cut at least one line of this grid. (Example : In Southwest corner of the grid the 2x2 area covers the squares a1-a2-b2-b1. Consider bK in a1 and wR in b1. King is not in check. Then wR moves to c1 (crossing one grid line, moving to another 2x2 area c1-c2-d2-d1) and gives check from there).
[Greek Σκακιέρα πλέγματος [ska-kie’-ra ple’-ghma-tos]]

Grotesque :
A problem or a study with very unnatural initial position, especially one with heavy position or with great difference of opponent forces. See here.
[Greek Γκροτέσκο [gro-te’-sko]]

Heavy :
An adjective applicable to a problem with too much material in the initial position. This situation must be avoided for reasons of Economy. See here.
[Greek Βαρύ [va-ri’]]

Helpmate :
A type of problem where white and black cooperate to mate black in a certain number of moves. Black plays first in helpmates. See here and here.
[Greek Βοηθητικό [vo-i-thi-ti-ko’]]

Hopper :
The piece that leaves a square, hops over an obstacle (a hurdle) and steps down on some square behind the obstacle. Example : the Grasshopper steps down on the first square behind the obstacle and possibly captures an opponent piece there. Example : the Locust steps down on any nonempty square behind the obstacle and captures it.
[Greek Εμποδιστής [em-po-di-sti’s]]

Illegal :
It is the problem where the given position cannot be the result of various legal moves after the initial placement of the 32 pieces (for playing a game). See here.
[Greek Παράνομο [pa-ra’-no-mo]]

Insoluble, or having no solution :
A problem that cannot be solved in the moves predefined in the stipulation. See here.
[Greek Άλυτο [a’-li-to]]

Interference :
The closing of a line of one piece from a second piece, thus limiting the mobility of the first and cutting its reach to certain squares. The various types of interferences are named, as Grimshaw intersection, Nowotny intersection, Anti-Bristol, Holzhausen intersection, Wuertzburg-Plachutta intersection and Plachutta intersection. See here.
[Greek Παρεμβολή [par-em-vo-li’]]

Intersection :
The square on which two lines (of movement of two linear pieces) are intersected. See here.
[Greek Διατομή [di-a-to-mi’]]

Intersection Grimshaw :
Mutual interference of two dissimilarly moving black linear pieces (R with B, or P with B) on the same empty square. For pieces P and B there is also the term Pickabish. See here and here and here and here.
[Greek Διατομή Γκρίμσο [di-a-to-mi’ gri’m-so]]

Intersection Holzhausen :
It is a square on which a black linear piece interferes with another black piece similarly moving, (R with R, B with Q), in another row (or file or diagonal). If the interference is mutual, it is called Wuerzburg-Plachutta intersection. When the pieces are on the same line we have the Anti-Bristol theme. See here.
[Greek Διατομή Χολτσχάουζεν [di-a-to-mi’ holts-ha’-u-zen]]

Intersection Nowotny :
A white piece is sacrificed on a Grimshaw intersection forcing black to capture it, thus resulting in the mutual self-interference of the black pieces. If white pieces of dissimilar linear movement are self-interfered, we have a White Nowotny intersection. See here.
[Greek Διατομή Νοβότνι [di-a-to-mi’ no-vo’t-ni]]

Intersection Pickabish :
It is a Grimshaw intersection where the pieces are Pawn and Bishop. See 033.
[Greek Διατομή Πίκαμπις [di-a-to-mi’ pi’-ka-bis]]

Intersection Plachutta :
A white piece is sacrificed on a Wuerzburg-Plachutta intersection forcing black to capture it, thus resulting in the mutual self-interference (two Holzhausen interferences) of the black pieces. See here.
[Greek Διατομή Πλαχούτα [di-a-to-mi’ pla-hu’-ta]]

Intersection Wuerzburg-Plachutta :
Mutual interference between two similarly moving linear pieces, moving on different lines. It is a pair of Holzhausen self-interferences. See here.
[Greek Διατομή Βίρτσμπουργκ-Πλαχούτα [di-a-to-mi’ vi’rts-burg pla-hu’-ta]]

Judge :
In composition (or solving) contests the responsibility for the definition of the theme (or the selection of the winners) belongs to respectable problemists, who are called Judges. See here.
[Greek Κριτής [kri-ti’s]]

Key :
The first and unique move that solves the problem. A problem having, despite the composer's will, another move that solves it, is considered useless, cooked. See Symbols of chessmen, Chess notation, (1) The Key, (2) The key, when it is considered not good, Characteristics : Sacrifice, promotion, Exposition to check, Unpin, Line opening, Flights, destroying battery, zugzwang, subpromotion, waiter, give and take, retroanalysis.
[Greek Κλειδί [kli-di’]]

Leaper :
The piece that steps from one square to another always covering the same distance. If it covers x squares on a row and y squares on a column, we call it a (x,y)Leaper. For example, the Knight is a (2,1)Leaper or (1,2)Leaper. (See Rider and Hopper).
[Greek Άλτης [a’l-tis]]

Legal :
It is a problem where the given position can be the result of various legal moves (not necessarily intelligent ones) after the initial placement of the 32 pieces (for playing a game). See here.
[Greek Νόμιμο [no’-mi-mo]]

Line clearance or Line opening :
The first piece leaves the square to allow the passing of the second (linear) piece over this (critical) square moving towards a destination square.
[Greek Εκκένωση γραμμής [e-ke’-no-si gra-mi’s]]

Light :
Adjective applicable to a problem having relatively small material in the initial position. This situation is desirable for reasons of economy. See here.
[Greek Ελαφρύ [e-la-fri’]]

It is a heterodox fairy condition, which specifies that if a piece is threatening a similar piece of the opponent (wR with bR, wS with bS, wB with bB, etc) then both pieces are paralyzed for as long as they are threatening each other. [Condition King Madrasi : the Madrasi condition is applicable to the Kings], [Condition Isardam : moves that result in Madrasi paralysis are not legal].
[Greek Μαντράσι [ma-dra’-si]]

Mate, Chameleon :
Chameleon mates are two echo mates, with the King on squares of different color. See 146.
[Greek Ματ Χαμαιλέων [mat ha-me-le’-on]]

Mate, Echo :
Echo mate are two mates which have in the solution mirror images. See 009.
[Greek Ματ Ηχώ [mat i-ho’]]

Mate, Economical :
Economical mate is a mate, where all the white pieces are taking part (with possible exception of King and Pawns). See 009.
[Greek Ματ Οικονομικό [mat i-ko-no-mi-ko’]]

Mate, Ideal :
Ideal or perfect mate is a pure mate where all the pieces of both colors cooperate to make it possible. See 045.
[Greek Ματ Ιδεώδες [mat i-dhe-o’-dhes]]

Mate, Mirror :
In a mirror mate all the squares around the mated King are empty. See 045.
[Greek Ματ Καθρέπτης [mat ka-thre’-ptis]]

Mate, Model :
The model mate is a pure and economical mate. See here.
[Greek Ματ Μοντέλο [mat mo-de’-lo]]

Mate, Pure :
Pure mate is the mate position, where the square of the mated King and all the neighboring squares, either each is observed by one enemy force or it is blocked by a friendly piece, (not threatened and blocked at the same time). (An exception is the pinned friendly piece which cannot move to intercept the check). See here.
[Greek Ματ Καθαρό [mat ka-tha-ro’]]

Maximummer :
A problem in which the pieces make the geometrically largest move they can, as it is measured from the center of the departure square to the center of the arrival square. If there are two or more largest moves, the player can select which one to play. Black Maximummer is the problem, where the maximummer condition is applicable only on black moves. This type of problem usually is a Selfmate problem.
[Greek Μαξιμούμερ [ma-xi-mu’-mer]]

Meredith :
A problem with 8 to 12 pieces in its initial position. See here.
[Greek Μέρεντιθ [me’-re-dith]]

Miniature :
A problem with 7 or less pieces in its initial position. See here.
[Greek Μινιατούρα [mi-nia-tu’-ra]]

More-mover :
When the moves of the solution are more than 3. For example, an orthodox with stipulation like White plays and mates in N moves (where N is a number greater than 3). See here.
[Greek Πολυκίνητο [po-li-ki’-ni-to]]

Mutate :
In a problem with complete block we cannot find a waiter key, thus we abandon at least one of the mates of the set play, so we have changed mates after the key. See here.
[Greek Αλλαγμένα ματ [a-la-ghme’-na mat]]

N :
In chess problems the letter N symbolizes the fairy piece Nightrider. In the English chess notation for problemists the letter N (from kNight) is used to symbolize the Knight.

Nightrider :
Popular fairy piece, rider type. See here.
[Greek Καβαλάρης της Νύχτας [ka-va-la’-ris tis ni’h-tas]]

Organ Pipes :
Arrangement of pieces BRRB in adjacent squares in a row. That creates four Grimshaw interchanges with eight self-interferences. See here and here.
[Greek Αυλοί του Αρμόνιου [av-li’ tu ar-mo’-ni-u]]

Originality :
If the theme and the position of a problem B have already appeared in a prior problem A, without having the composer B knowledge of this fact, then the problem B is considered anticipated (not original). The position might not be exactly the same, it is enough to be similar. If this is done by the composer B on purpose, then we talk about plagiarism (theft). The possibility of a problem to be anticipated, is very high if the theme of the problem is simple and the pieces few, since chess problems are being created for hundreds of years now. The judges of the contests have enormous experience and they usually use computers with large databases to check originality. See Originality and Economy.
[Greek Πρωτοτυπία [pro-to-ti-pi’-a]]

Over-The-Board playing of the game of Chess :
Two players, White (plays first) and Black, play alternatively. It is quite different from Chess Composition, where a composer creates a problem and in a later time a solver tries to discover its solution. See OTB chess vs compositions.
[Greek Αγωνιστικό σκάκι [a-gho-ni-sti-ko’ ska’-ki]]

Pericritical :
Moves focused on a critical square. See here.
[Greek Περικρίσιμες [pe-ri-kri’-si-mes]]

Phase of play:
One phase is "the moves of the set play before the key". Another phase is "the moves after a try". Another phase is "the moves after the key". A direct mate problem with set play is a bi-phase problem. An orthodox problem with three tries is a four-phase problem. The play in one phase may be (thematically) relevant with the play in other phases. See here.
[Greek Φάση παιγνιδιού [fa’-si pe-ghni-dhiu’]]

Pickabish :
Special name for Grimshaw intersection with Pawn and Bishop.
[Greek Πικαμπίς [pi-ka-bi’s]]

Proof or Retrograde analysis or Retroanalysis :
Reasoning about the move (or the moves) before the specified position. The problem might focus on finding the Shortest Proof Game (SPG), or the stipulation might be [find the last move of black], or the Retroanalysis may be part of a greater problem. For example, it may be necessary to prove that the black King has been moved before the given position, so black has no right for castling. See here and here and 157 159 160.
[Greek Αποδεικτική ανάλυση, [a-po-di-kti-ki’ a-na’-li-si]]

Proof Game, PG) :
A kind of problem where a position is given to the solver and he/she must discover the actual moves of the game, starting from the classic initial placement of the pieces, and reaching the given position in a specified number of moves. Is is a kind of Retroanalysis. See here.
[Greek Αποδεικτική παρτίδα [a-po-di-kti-ki’ pa-rti’-da]]

Reflexmate :
A selfmate in which both sides are forced to give mate, if it is their turn to play and they can give mate. If this limitation is applicable only on black, the problem is called semi-reflexmate.
[Greek Ρεφλέξ-ματ [re-fle’x mat]]

Revealer :
A piece that reveals, by its presence or placement, the way to solve the problem. See here.
[Greek Μαρτυριάρης [mar-ti-ria’-ris]]

Rex solus :
Problems where the King is alone. See here.
[Greek Ρεξ σόλους [rex so’-lus]]

(r,c)Rider :
The piece which moves on a line, without passing over an obstacle. It is an (r,c)Leaper of multiple steps, where r symbolizes squares on row and c symbolizes squares on column for each step. Examples are the Rook and the Bishop. The Rook is a (0,1)Rider or (1,0)Rider. The Bishop is a (1,1)Rider.
[Greek Δρομέας [dro-me’-as]]

Round trip (German, Rundlauf) :
A piece departs from a square and later in the solution returns on it after a polygonal path (for example : a Rook follows the path e3-g3-g5-e5-e3). Special cases are the Triangle of the King and the Triangle of the Queen. Compare the round trip with the Switchback, where the path is on one line.
[Greek Ταξίδι με επιστροφή [ta-xi’-dhi me e-pi-stro-fi’]]

Royal battery :
The royal battery is formed when the front piece of the battery is the white King. (The King side-steps, opening the line for the back line piece to act). Task is when the royal battery fires with six different ways in orthodox problems (eight ways in heterodox problems!). See 044.
[Greek Βασιλική Μπαταρία [va-si-li-ki’ ba-ta-ri’-a]]

S :
In chess problems the letter S symbolizes the Knight (from the German Springer (= knight)).

Self-block :
The flights of the black King are blocked by black pieces. See 120.
[Greek Αυτομπλοκάρισμα [af-to-blo-ka’-ri-sma]]

Selfmate :
Heterodox problem, where white forces the non cooperative black to deliver mate to white, in a certain number of moves. See here and here.
[Greek Αντίστροφο [a-nti’-stro-fo]]

Series-mover :
A problem where the one side makes a series of moves without answers from the other side, except in the last move. The target may be win of White, stalemate, or win by Black. See 099.
[Greek Σειράς κινήσεων [si-ra’s ki-ni’-se-on]]

Set play :
Moves that could be played from the initial position of the problem, if the other color was to play. The Set play is a Phase of the solution. For example, in an Orthodox problem, the Set play consists of series of moves starting with a black move (white has not played yet). When Set play exists, then (a) the key move of white does not change the series of moves and the problem is a Perfect Block, or (b) the key changes the mate formations and the problem is a mutate. See 038.
[Greek Έτοιμο Παιγνίδι [e’-ti-mo pe-gni’-di]]

Square vacancy :
Emptying of a square. The first piece leaves the square to allow the move of the second piece to this square.
[Greek Εκκένωση τετραγώνου [e-ke’-no-si te-tra-go’-nu]]

Study :
Orthodox problem without limit on movements. See here and here.
[Greek Σπουδή [spu-di’]]

Subpromotion :
A Pawn making its seventh step reaches the last row and there it is promoted to any piece, existing in the initial placement or initial position of the problem, Except King or Pawn. See 009 and here.
[Greek Υποπροαγωγή [i-po-pro-a-gho-ghi’]]

Switchback :
A piece leaves a square and later in the solution comes back on it and all moves are made on one line (for example, a Rook follows the path e3-e5-e3). Compare this with the Round-trip, where the path is polygonal. See 006 168.
[Greek Επιστροφή [e-pi-stro-fi’]]

Symmetry :
The position appears symmetric. The solution is not necessarily symmetric. See here.
[Greek Συμμετρία [si-me-tri’-a]]

In a problem some theme is used in its extreme, and we say a task has been achieved. For example, it is a task when the Royal Battery gives mate opening with the maximum number of ways. See here and here and here.
[Greek Άθλος [a’-thlos]]

Tempo :
The expression I win tempo (=I win time) means that I win moves : Either I can achieve something in less moves, or the opponent delays to reach his goal which is equivalent with giving to me extra moves.
[Greek Τέμπο [te’-mpo]]

Theme :
Defines the target of the composer, that is what the composer wanted to achieve creating the problem, what idea is hidden in the problem. See here.
[Greek Θέμα [the’-ma]]

Theme WP4 :
A white pawn standing on its initial square, in four variations of the solution makes its four possible moves (one step forward, two steps forward, capture left, capture right). See here and here.
[Greek Θέμα ΛΠ4Κ

Theme Allumwandlung or AUW (from German) (=Multiple pawn Promotions) :
The solution contains pawn promotions to all kind of pieces. In orthodox problems we have quadruple promotion, to Queen, Rook, Bishop, Knight. See here 015 016. In Fairy chess the theme can be expanded to promotions of fairy pieces, present in the initial diagramme of the problem. See a super-AUW at 241.
[Greek Θέμα Πολλαπλή προαγωγή [the’-ma po-la-pli’ pro-a-gho-ghi’]]

Theme anti-Bristol :
Like the Theme Bristol, but the first piece does not facilitates the second piece, but becomes an obstacle.
[Greek Θέμα Αντι-Μπρίστολ [the’-ma an-ti-bri’-stol]]

Theme Arguelles :
A black line of influence is neutralized with energetic and with pathetic interference. See 226.
[Greek Θέμα Αργκίλες [the’-ma ar-gi’-les]]

Theme Babson :
White plays first. Black defends with four promotions (Q, R, B, S) (AUW allumwandlung). White answers with four corresponding promotions (Q, R, B, S). See here.
[Greek Θέμα Μπάμπσον [the’-ma ba’b-son]]

Theme Berlin :
A move, which gives mate in a try, becomes a simple check in the actual play. See 244.
[Greek Θέμα Βερολίνου [the’-ma ve-ro-li’-nu]]

Theme Bicoloured Bristol :
It is similar to Theme Bristol but with pieces of both colors.
[Greek Θέμα Δίχρωμο Μπρίστολ [the’-ma dhi’-hro-mo bri’-stol]]

Theme Bicoloured Cheney-Loyd :
the piece A makes a critical move and the piece B of different colour goes to the critical square and interferes. See here.
[Greek Θέμα Δίχρωμο Τσένεϊ-Λόιντ [the’-ma dhi’-hro-mo tse’-ne-i lo’-id]]

Theme Bicoloured Turton :
It is similar to Theme Turton but pieces A and B are of different colors. See here.
[Greek Θέμα Δίχρωμο Τέρτον [the’-ma dhi’-hro-mo te’r-ton]]

Theme Bikos :
In one phase, in one variation a self-block is exploited and in another variation the moving piece is taken. In another phase, the same two defenses have reciprocal continuation. See here 011 126.
[Greek Θέμα Μπίκος [the’-ma bi’-kos]]

Theme Bivalve :
The black, opening a line of one black piece, closes another line of another black piece. See here.
[Greek Θέμα Διπλοβαλβίδα [the’-ma dhi-plo-val-vi’-dha]]

Theme Black-Bristol :
Similar to Theme Bristol, but with black pieces.
[Greek Θέμα Μαύρο-Μπρίστολ [the’-ma ma’-vro bri’s-tol]]

Theme Black Cheney-Loyd :
the black piece A makes a critical move and the black piece B goes to the critical square and interferes. See here.
[Greek Θέμα Μαύρο Τσένεϊ-Λόιντ [the’-ma ma’-vro tse’-ne-i lo’-id]]

Theme Brede cross-checks :
Every black check is answered with white check that pins the white piece, which then is unpinned and delivers mate. See here.
[Greek Θέμα Μπρέντε Διασταυρωμένα σαχ [the’-ma bre’-de dhi-a-sta-vro-me’-na sah]]

Theme Bristol line clearance :
It is a two-move theme. The first white linear piece moves towards one direction opening the way for the second white linear piece to move towards the same direction. If the first piece is not participating to the mate, it is called parasitic. For black pieces the theme is called Theme Anti-Bristol. See here.
[Greek Θέμα Μπρίστολ [the’-ma bri’s-tol]]

Theme Brunner-Turton doubling :
Similar to Theme Turton, but the pieces A and B are of equal strength. See here.
[Greek Θέμα Μπρούνερ-Τέρτον [the’-ma bru’-ner te’r-ton]]

Theme Checking key :
In orthodox problems is generally avoided, but in other kinds (helpmates, selfmates, fairy) is acceptable. See here.
[Greek Θέμα Σαχ στο κλειδί [the’-ma sah sto kli-di’]]

Theme Cheney-Loyd :
A white piece A makes a critical move and then a white piece B goes to the critical square and interferes. See here, 022.
[Greek Θέμα Τσένεϊ-Λόιντ [the’-ma tse’-ne-i lo’-id]]

Theme Dombrovskis :
In the post-key play at least two defenses, which have refuted some threats of the tries, are subdued with exactly the same threats of the tries. See here and here.
[Greek Θέμα Ντομπρόβσκι [the’-ma do-bro’v-ski]]

Theme Dresden :
The move of a black piece changes the (good) defense of piece-A to (inadequate) defense of piece-B. See 077.
[Greek Θέμα Δρέσδης [the’-ma dhre’s-dhis]]

Theme Excelsior :
A Pawn moves from its initial square to its promotion square. See 114 115.
[Greek Θέμα Εξέλσιορ [the’-ma e-xe’l-si-or]]

Theme Fleck :
The key introduces multiple threat, at least triple. In each variation the defense of the black leaves only one threat valid. See 010.
[Greek Θέμα Φλεκ [the’-ma flek]]

Theme Focal play :
A black linear piece (Queen, Rook, Bishop) focuses on two squares in two different directions, but when it moves it is forced to lose focus and abandon the guarding of one of the squares. See here.
[Greek Θέμα Εστιακό Παιγνίδι [the’-ma es-ti-a-ko’ pe-gni’-dhi]]

Theme Hamburg :
The move of a black piece changes the way of defense of another piece. See 077.
[Greek Θέμα Αμβούργου [the’-ma am-vu’-rgu]]

Theme Indian :
A critical white piece makes a critical move and passes over a critical square. Then a white piece self-interferes on the critical square to avoid stalemate of the black and in the next move withdraws giving check by discovering of the critical piece. See here and 127 128 137.
[Greek Θέμα Ινδικό [the’-ma in-dhi-ko’]]

Theme Java :
two squares adjacent to bK are controlled by two white pieces each. Black closes one line of control and white cannot close the other line of control, thus white selects the next move avoiding dual. See 356.
[Greek Θέμα Ιάβα [the’-ma i-a’-va]]

Theme Karlstroem-Fleck :
The key introduces multiple threat, at least triple. The defense of the black separates the threats, and in each variation only one remains valid. There is at least one black move that is defense for all threats of the key, but allows some other mate. See 010 049.
[Greek Θέμα Κάλστρεμ – Φλεκ [the’-ma ka’l-strem flek]]

Theme Lacny pxv.
It is developed over various phases (the number of phases is p). In one phase there are some (a b c ... z) defenses (the number of variations is v) which are answered with the mates (A B C ... Z). In another phase the same (a b c ... z) defenses are answered with a cyclic permutation of the mates (B C ... Z A). See 212.
[Greek Θέμα Λάσνι [the’-ma la’-sni]]

Theme Loyd-Turton doubling :
Similar to Theme Turton, but piece A is stronger than piece B. See here.
[Greek Θέμα Λόιντ-Τέρτον [the’-ma lo’-id te’r-ton]]

Theme Martin I :
Two black pieces are half-pinned. Each piece attempts corrective defense. The primary and secondary mates are relevant with the other half-pinned piece which is now pinned. See here.
[Greek Θέμα Μάρτιν 1 [the’-ma ma’r-tin e’-na]]

Theme Martin II :
The corrective defenses are exploiting the unpin of a third black piece.
[Greek Θέμα Μάρτιν 2 [the’-ma ma’r-tin di’-o]]

Theme Phoenix (Phénix) :
A pawn is promoted to a piece which was previously captured. See here.
[Greek Θέμα Φοίνιξ [the’-ma fi’-niks]]

Theme BP4 :
A black pawn standing on its initial square, in four variations of the solution makes its four possible moves (one step forward, two steps forward, capture left, capture right). See here and here.
[Greek Θέμα ΜΠ4Κ]

Theme Pronkin :
A promoted piece goes to the initial square of an identical captured piece. See here.
[Greek Θέμα Πρόνκιν [the’-ma pro’n-kin]]

Theme Roman :
A black piece, which can defend adequately, is relocated to a square, from where it can defend again, but not sufficiently. See here and here.
[Greek Θέμα Ρωμαϊκό [the’-ma ro-ma-i-ko’]]

Theme Stavrinides :
The (compact algebraic) notation of white and black moves shows circular transposition. (See here). [Theme shown in one phase : 1. K!, 1...Aaa 2. Bbb#, 1...Bbb 2. Ccc#, 1...Ccc 2. Aaa#], [Theme shown in tries : 1. Aaa? Bbb!, 1. Bbb? Ccc!, 1. Ccc? Aaa!].
[Greek Θέμα Σταυρινίδης [the'-ma sta-vri-ni'-dis]]

Theme TRD :
It is a double Grimshaw, which is formed from two Rooks and a Bishop, or from two Bishops and a Rook. (The theme is also called Three Rider Double). See 060.
[Greek Θέμα Τι-αρ-ντί [the’-ma ti-ar-di’]]

Theme Turton doubling :
A linear piece A moves beyond a critical square, permitting to a like-coloured and stronger piece B to move onto the critical square. Later, piece B moves on the same line to the opposite direction, being supported by piece A. See here.
[Greek Θέμα Τέρτον [the’-ma te’r-ton]]

The problem contains all the "strange" chess moves, that is castling, (sub-)promotion and en-passant capture. See 159.
[Greek Θέμα Βαλαντάο [the’-ma va-la-nta’-o]]

Theme Valve :
The black opens a line for one of his pieces, closing another line of the same piece. See here.
[Greek Θέμα Βαλβίδα [the’-ma val-vi’-dha]]

Theme X-flights :
The King can escape moving diagonally (northeast, northwest, southwest, southeast). See here 015 and 029.
[Greek Θέμα Διαφυγές-Χ [the’-ma di-a-fi-ge’s hi]]

Theme Zappas :
A flight of the black King is guarded by three white pieces. There are three tries which fail, as a result of the cyclic neutralization of the three guards by the White and the Black. See here.
[Greek Θέμα Ζάππας [the’-ma za’-pas]]

Theme Zepler-Turton doubling :
Initially the piece A moves. Then piece B steps on the critical square. Then piece A moves again, being supported by piece B. See here.
[Greek Θέμα Τσέπλερ-Τέρτον [the’-ma tse’-pler te’r-ton]]

Theme Zilahi :
Black captures the white piece, which checkmates in the other solution. See 096.
[Greek Θέμα Ζίλαχι [the’-ma zi’-la-hi]]

Threat :
It is the move (or the series of moves) which white is threatening to play (usually after the key) if black does not present some suitable defense. Problems with no threat after the key have complete block of the black, the key is called waiter key and the black is in a hopeless (german term zugzwang, zz) situation.
[Greek Απειλή [a-pi-li’]]

Three-mover :
An orthodox problem with stipulation Mate in 3.
The threemovers of other types always have a characteristic, as helpmate threemover, selfmate threemover, etc.. See here.
[Greek Τριάρι [tri-a’-ri]]

Try :
A first move that almost solves the problem, but there exists a unique defense. The series of moves after the try are called virtual play. The virtual play after a try is one Phase of the solution. The existence of tries makes more difficult the work of the solver, who seeks to discover the key, and it is an important element of the beauty of the problem. See here.
[Greek Δοκιμή [do-ki-mi’]]

Twins :
Two (or more) problems which (a) have small differences, (b) have different solutions, and (c) are composed by the same person. The difference might be addition or removal or relocation of one piece in the position of the first problem, "sliding" the position by one row or one column, alteration of the stipulation from direct-mate to helpmate, etc.. See here.
[Greek Δίδυμα [di’-di-ma]]

Two-mover :
An orthodox problem with stipulation [White plays and mates in two moves, despite the good defense of the Black] or simply [Mate in 2]. The two-movers of others categories have always a characteristic (helpmate two-mover, selfmate two-mover). See here and here.
[Greek Δυάρι [dhi-a’-ri]]

Unprovided check :
In the initial position there is a check by Black that reveals what the key should be. It is a flaw, since it diminishes the difficulty of the problem. See 215.
[Greek Αναπάντητο σαχ [a-na-pa’-nti-to sah]]

Variation :
A series of moves from the key thru the final target (win, stalemate, etc). See here.
[Greek Βαριάντα [va-ria’-nta]]

Version :
It is a problem, which is a modification of a previous problem. The problem might be modified for economy reasons, or for elimination of a defect (a cook, a second solution), or because of No solution. See here and here.
[Greek Διασκευή [di-a-ske-vi’]]

Virtual play :
It is the play after a try.
[Greek Εικονικό παιγνίδι [i-ko-ni-ko’ pe-gni’-di]]

Zagoruyko :
In at-least three phases and in at least two, always the same, defenses of the black, the continuations of white change. It is a presentation frame which can be combined with various themes. See here 240 324.
[Greek Ζαγκορούικο [za-go-ru’-i-ko]]

Zugzwang or zz:
Black is not under threat, but it is Black's turn to play. The bad news is that any black move makes Black's position instantly worse. This is called blockade or more commonly zugzwang situation. See here and 034.
[Greek Τσούκτσβανγκ [tsu’k-tsvang]]

(This post in Greek language).

Saturday, June 14, 2008

Solving Contest, 2008-04-19, ESSNA Pagrati

 Left to right : Papastavropoulos, Anemodouras, Garoufalidis, Ilandzis, Mendrinos, Konidaris.

The 5th Solving Contest of E.S.S.N.A. (Union of Chess Clubs in Prefecture of Attica), contest surnamed "Byron Zappas", was successfully held in Chess Club of Pagrati in Saturday, April 19.
Eighteen solvers participated, having 2h 15m available time to solve 6 problems (1 two-mover, 1 three-mover, 1 four-mover, 1 study, 1 helpmate and 1 selfmate). The contest was dedicated to the top Greek composer of chess problems Byron Zappas, who died this year. All the compositions of the contest were created by Greek problemists.

The following persons gathered the most points :
1. Nikos Mendrinos (25 grades in 30) champion of Attica,
2. Andreas Papastavropoulos (20),
3. Panagiotis Konidaris (19),
4. Leocratis Anemodouras (15),
5. John Garoufalidis (15),
6. Spyros Ilandzis (14).

Best team proved to be "Zinon Glyfadas". No prize for category "young under 20 years old" was given.

The judge of the contest, Panagis Sklavounos, selected the following problems by Greek composers.

 (Problem 148) Marassoglou N., 'To Mat', 1952 Mate in 2 #2 (7+4) [K3k3/P2R4/2p5/2B1P1p1/6B1/1r6/Q7/8]

 (Problem 149) Zappas Byron, Parallèle 50, 1948 Mate in 3 #3 (8+5) [8/1p3R2/1pBp4/2kS1p2/RS6/1K1P4/P7/8]

 (Problem 150) Siaperas T., Problem, 1952 Mate in 4 #4 (8+9) [K5S1/1p3s2/4kS1p/p2R4/3PP1Rp/5Bb1/5s1q/8]

 (Problem 151) Fragoulis K., Suomen Shakki, 1978 White plays and wins + (4+3) [8/4pK2/8/pk6/SS6/8/1P6/8]

 (Problem 152) Paizis K., B.C.M., 1993 Helpmate in 3, (two solutions) h#3 (3+3) 2.1.1.1 [1K3b2/4s3/5P2/4k1S1/8/8/8/8]

 (Problem 153) Moutecidis P., Gazeta Czestochowska, 1970 (Set play). Selfmate in 2 (*) s#2 (11+14) [4b3/S1PkPP1R/3p4/3B4/4RPPp/2ppB1pq/3p2pB/3K1srr]

Here are the solutions of the problems:

Problem-148, Marassoglou, #2
Tries: {1.Rd1? / Rd2? / Rd3? / Rd4? Kf7!}, {1.Rb7? Kd8!}, {1.Ba3? / Bb4? / Bd6? c5!}, {1.Bh3? / Bf5? g4!}, {1.Bh5+? Kxd7!}, {1.Qb1? Rxb1!}, {1.Qa6? Rb7!}, {1.Qa5? Rb6!}, {1.Qf2? Rf3!}
Key: 1.Rc7! (zz).
Variations: 1...Kd8 2.Rc8#, 1...Rb8+ 2.axb8=Q# / axb8=R#, 1...R~ 2.Rc8# / Qg8#, 1...Rd3 2.Qg8#, 1...Rf3 2.Rc8#.

Problem-149, Zappas, #3
Tries: {1.Rxf5? / Rxb7? / Be8? / Bd7? / Bxb7? Kd4!}, {1.d4+? Kxd4!}, {1.Sa6+? Kxc6!}, {1.Kc3? bxc6!}.
Key: 1.Kc2! [2.d4+ Kxd4 / Kc4 3.Sd3#]
Variations: 1...Kd4 2.Sa6+ Ke5 3.Re7#, 1...b5 2.Kc3 and 3.d4#, 1...bxc6 2.Rxf5 (zz) Kb5 / Kd4 / b5 / cxd5 3.Sc3# / Sa6# / Sa6# / Rxd5#.

Problem-150, Siaperas, #4
Try: {1.Rd7? Bd6!}
Key: 1.Rg7! [2.Bh5 ~ / Sf7~ (if black plays anywhere or if he plays somewhere with Sf7, then) 3.Bxf7# / Re7#]

If 1...Bb8 (Bristol line clearance)
2.Bh5 Qc7 (we understand now that the black pawns a5 and b7 were placed there to void checks from the black Queen Qc7)
3.Bg6 [4.Bf5#]
3...Qf4 / Qe5 4.Bxf7#
3...Sd6 4.Re5# (Note that in the initial position this square was guarded by three black forces!).

If 1...Bd6
2.Bh5 [3.Bxf7#]
2...Se5 3.dxe5 [4.Bf7#] Sxe4 4.Bg4#
2...Sg5 / Sh8 / Sd8 3.Be8 and 4.Bd7#

Problem-151, Fragoulis, study +
Key: 1.Sc2! Kxa4 2.Sa1!
2...Kb4 3.Kxe7 a4 4.Kd6 a3 5.Sc2+ ~ 6.bxa3 and white wins
2...e5 3.Ke6 e4 4.Kd5 e3 5.Kc4 e2 6.Sc2 e1=Q 7.b3#

Problem-152, Paizis, h#3 2.1.1.1
1.Kxf6 Se4+ 2.Kf7 Kc7 3.Ke8 Sd6#
1.Sg8 f7 2.Bc5 fxg8=Q 3.Kd6 Qe6#

Problem-153, Moutecidis, s#2 (*)
Phase of set play : (*)
1...Kxc7 2.fxe8=Q (zugzwang, zz, and black is forced to continue by giving mate) Sxe3# / c2# / Qxg4#
1...Bxf7 2.e8=S (zz)

Tries: {1.Rh5? / Rh6? / Rh8? Bxf7!}, {1.c8=B+? Kc7!}, {1.Bc6+? / f8=S+? Kxc7!}, {1.fxe8=Q+? / fxe8=S? / fxe8=R? Kxe8!}.

Phase of real play : Key: 1.Sb5! (zz)
1...Kc8 2.fxe8=B (zz)
1...Bxf7 2.e8=R (zz)

Since it has achieved the four promotions in the solution, the problem is an allumwandlung (AUW).

(This post in Greek language).

Friday, June 13, 2008

Grasshopper

The Grasshopper, (German Grashüpfer, French Sauterelle), is a popular fairy piece, which was invented in 1912 by the British founder of the Fairy Chess Thomas Rayner Dawson.
The Grasshopper, which in diagrams has the symbol of an upside-down Queen and in texts the letter G, belongs in the category of the hoppers. It moves on a line or diagonal (just like the Queen) towards a piece (obstacle or hurdle) and steps down on the the square exactly behind the hurdle.
If the Grasshopper is on a8 and there is another piece on a2, the Grasshopper can move to square a1. If there is an enemy piece on the arrival square, the Grasshopper captures it. The piece on a2, which were used as a hurdle for the hopping of the Grasshopper, is not affected. If there are no hurdles for the Grasshopper to jump over them, (or the Grasshopper 'sees' on its lines of movement various pieces, but they have behind them other pieces, having same color as the Grasshopper), the Grasshopper cannot move.
The Grasshopper is a linear piece strategically interesting. We can interpose on a5 a piece and the Grasshopper Ga8, which were threatening the square a1 using as hurdle the piece on a2, now is threatening the square a4 because it can hop over the piece on a5. Also, a battery with a Grasshopper is not firing after removing the front piece , but it is formed and fired by placing in front of the Grasshopper a piece.
If there are Grasshoppers in the initial position of a problem, then a pawn may be promoted to Grasshopper.

 (Problem 106) T. R. Dawson, British Chess Magazine, 1943 Mate in 2. (Grasshoppers). #2 (6+8) 1+3 grasshopper [8/7p/7K/1g2Sbp1/G3g1Sk/2B3gp/8/6s1]

The Grasshopper Gb5 is threatening Bf5.
The Grasshopper Ga4 can move to c6 and f4.
The Grasshopper Ge4 can move to e6 and g6 (not to h4).
The Grasshopper Gg3 can move to b3 and d6 (not to g5).
The Grasshopper Ga4 keeps the Ge4 pinned because, if Ge4 is lifted, then Ga4 is threatening Kh4 which is exactly behind the hurdle Sg4.

There are some tries: {1.Bxe4? [2.Be4~#] Se2!}, {1.Sf3+? Sxf3!}, {1.Sg6+? hxg6!}, {1.Sh2? Gxf5!}, {1.Gf4+? gxf4!}.

Key: 1.Se3!
It so happens that the key unpins Ge4 (!), but black is in zugzwang.
In the next three variations white forms a battery arriving on the line of Ga4, and removing at the same time the hurdle of the black G which has moved but it cannot come back!
1...Ge6 2.S5g4# (if Ge6xg4 is played, the Grasshopper from e6 becomes the hurdle for Ga4).
1...Gg6 2.Bg4#
1...Ge2 2.S3g4#

Other variations:
1...Sg1~ 2.S(x)f3#,
1...Gg3~ 2.Be1#,
1...h2 2.Sg2#,
1...Gxf5 2.Sxf5#,
1...g4 2.Gf4#.

In the next problem-147, by the IM Harry Fougiaxis, we observe in the two solutions similarity of movements on the file or on the diagonal (orthogonal-diagonal echo), where the black Grasshoppers win the needed tempo with the key:

 (Problem 147) Harry Fougiaxis 434 Sinfonie Scacchistiche No. 91-82, 06/1988 Helpmate in 2, two solutions h#2, 2.1.1.1, (5+5), 2+2 grasshopper [4G3/G7/2K1S3/2S5/3ggp2/3pk3/8/8]

By examination of this position, we locate two sequencies of moves in the set play:
1...Sg5+ 2.Ge2 Se4# (First check is discovered and the mate is made with double checking).
1...Sb3+ 2.Gf2 Sd4# (Similar mechanism with the previous one, but on the diagonal).

Look now where black will find the move to win one tempo:
1.Ge7! Sg5 2.Ge2 Se4#
1.Gb6! Sb3 2.Gf2 Sd4#

(This post in Greek language).

Monday, June 09, 2008

Fairy chess

In Fairy chess belonged (in the beginning of the twentieth century) all the heterodox types of problems. When the helpmates and the selfmates became common enough, they were still heterodox but stopped being considered as part of the fairy genre of chess.
Today inside the realm of fairy chess remain the problems (a) with fairy pieces, (b) with fairy conditions, (c) with fairy chess boards, (d) with retroanalysis, (e) with constructive tasks.
Some fairy problems have excellent ideas in them and it is a pity that the fairy type is not widely known. The advanced solvers find great pleasure studying the solutions of the fairies.
The fairy problem composers have smaller risk that their creation will be anticipated.

(a) Pieces
The basic pieces are six : K Q R B S P . The fairy pieces are more than a thousand. Some pieces are interesting and are being used by many composers, some other pieces are just curious proposals. The fairy pieces are different from the basic in the way of movement or some other property, and they extend the possibilities of the problemists in new unexplored areas.
Trying to divide the pieces in categories, we find three basic categories, (Leapers, Riders, Hoppers), but there exist some pieces not belonging to any of those three.

First category, we have the leapers, pieces which move from a square to a certain distance, without being hindered by intermediate pieces. When a leaper is giving check we cannot intercept it.
In this category we already know the Knight. If we suppose that the Knight is in the center of a square having side equal to [1], then it can jump to the center of a square at a distance [square root of 5].
We can specify with two numbers (r,c) how many squares on the row and how many squares on the column the leaper can move. Sometimes the move with capture may be different from the move without capture.
S: The Knight is leaper (2,1) or (1,2) and with each step goes to a differently colored square.
C: The Camel is leaper (3,1) or (1,3) and stays on same colored squares.
Z: The Zebra is (3,2) or (2,3) and goes to a differently colored square.
K: The King is a hybrid leaper (1,0) or (1,1).

Second category, we have the riders, which have linear move and are hindered from intermediate pieces. With riders we create pins and interceptions.
We can specify with two numbers (r,c) how many squares on the row and how many squares on the column each step of the rider is. The riders are multi-stepping leapers. Sometimes the move with capture may be different from the move without capture.
B: The Bishop is rider (1,1) and stays on same-colored squares.
R: The Rook is rider (1,0) or (0,1).
Q: The Queen is a hybrid rider (1,1) or (1,0).
P: The Pawn moves as rider (0,1) or (0,2) and captures as rider (1,1), always going away from its initial square.
N: The Nightrider is rider (2,1) or (1,2).

Third category, there are the hoppers, which can move only if an intermediate piece exists, over which they hop. This intermediate obstacle can also be called "a hurdle".
G: The Grasshopper moves like the Queen and steps just behind the hurdle, where it can capture an opponent piece. (The Rook in castling makes a move like a Grasshopper).
L: The Locust moves almost like the Grasshopper, but captures the hurdle and steps to any square after the hurdle, if the line is open.

Of great interest are the composite pieces. We already know the Queen, which moves and captures like Rook or Bishop. There is also the Empress combining properties of Rook and Knight, and the Princess combining properties of Bishop and Knight. Another way of combining properties can produce pieces like, QS which moves like a Queen but captures like a Knight, RS which moves like a Rook but captures like a Knight, BS which moves like a Bishop but captures like a Knight, etc..

From the Chinese chess (xiangqi) come Mao, Vao, Pao and Leo.
M: The Mao moves like a Knight but it is not a leaper. It moves, going away from its position, making a step like Rook and then a step like Bishop. If the square of the first step is occupied, the Mao cannot move.
V, P, Le: The Vao, Pao, Leo move respectively like Bishop, Rook, Queen. The difference is that when they are going to capture, they are hoppers (must hop over a hurdle).

Royal piece is the one which must not be lost, because this loss is ending the game. In normal chess there is only one, the King. In fairy chess, more than one royal pieces can coexist having the same color. If a Knight is specified to be royal piece, it will move or capture as Knight, but it will accept checks and will be in endangered as a King.

(b) Fairy conditions
Fairy conditions are continuously invented. Some conditions hold the interest of the composers only for a short time. Some other conditions, as Circe or Madrasi, are very often appearing in composition contests (and we will see more of these conditions in future posts).

In Circe chess, every captured piece is reborn on its initial square. If the square is occupied, the piece is lost. For example, initial square for a white Rook is a1 or h1. If the Rook is captured on a white square, it will be reborn on h1. If the Rook is captured on a black square, it will be reborn on a1. Similar rules are valid for Bishop and Knight. The pawn is reborn on the initial square (line-2 for white pawns, line-7 for black) of the column on which it was captured. On normal Circe the King is not included in the condition. There is another condition including the King, Circe Rex Inclusiv.
There are several variations of the Circe rules.

In Madrasi chess, if a piece threatens another piece of the same type but of different color, then both are paralyzed. The only ability left to these pieces, is to paralyze one another. In normal Madrasi the King is not included in the condition. There is another condition including the King, Madrasi Rex Inclusiv.

When the condition Series of moves is valid, (we have already seen Series helpmate), one of the two sides makes a series of moves and then the other side answers with one move to fulfill what the stipulation has specified.

(c) Fairy chessboards
The cylindrical chessboards were very popular in the beginning of the twentieth century.
An horizontal cylinder has file-h in contact with file-a.
A vertical cylinder has in row-8 in contact with row-1.
The combination of the two cylinders is called torus or anchor ring.
There are chessboards which are not square-shaped, or having another (different than 64) number of squares.
In a special category we find the three-dimensional chess (3d-chess), like the one played by Mr. Spock in the TV series "Star Trek".

(d) Retroanalysis
In the category of retroanalysis (or retro) belong the problems, for which we need to discover what had happened in previous moves. We may seek the sequence of moves which led to the given position, as in the proof games, or we may wish to prove that an option is valid (for example, castling) for one or both opponents.