Albino: A white pawn, on its starting rank, makes each of its four possible moves in turn – two forward steps and two captures – during the course of the solution.
Allumwandlung (often abbreviated to AUW): The four possible types of promotion – to Queen, Rook, Bishop, and Knight – all take place during the course of the solution.
Anti-Balbo: Refutations and try keys are made by pieces of the same kind.
Balbo: Black moves are followed by moves of a white unit of the same kind.
Bristol: A theme consisting of the following line-clearance manoeuvre. A long-range piece moves along a line, crossing over a critical square, to enable another long-range piece of the same colour to access that square by following on the same line.
Ceriani-Frolkin: usually in a proofgame, a promoted piece is captured
Changed mate (continuation): 1…a 2.A / 1…a 2.B
Critical move: A line-moving piece moves beyond a square on which it will be intercepted, or to avoid to be intercepted (in that case, the expression "anticritical move" is also used)
Circuit: A piece returns to a previously occupied square after it occupied at least 2 other squares
Correction: White correction: A random move by a white unit has one or more helpful effects, but it is refuted by a black move. A specific move by the same white unit has the same helpful effects, but also a new effect which renders the black defence useless. Black correction: a random move by a black piece has a harmful effect which allows a white continuation to work. Another black move has the same harmful effect, but also a positive effect which prevents that white continuation from working. However, a second harmful effect allows another white continuation to work. If a third black move contains these harmful effects, positive effects preventing both white continuations from working, and a third harmful effect allowing a third white continuation to work, the black correction is tertiary.
Dalton: The key is made by a piece „A” which unpins a piece „a”. In the variation, „a” pins „A”.
Dentist: A black piece indirectly unpins a white unit. Then, that white unit moves and the so created black battery plays.
Djurasevic: in a twomover, the following pattern: 1.A?(2.B#)1…x 2.C# / 1.B!(2.C#) 1…x 2.A#
Dombrovskis: A directmate theme in which certain moves recur in the try play and actual play, but with their functions changed in a paradoxical way. In a two-mover, the solution follows this pattern: a white try threatens the mate 2.A, and is refuted by the black defence 1…x!; but after the key, it is this defence 1…x that enables White to mate with 2.A.
Dual avoidance: 2 black moves a and b have the same harmful effect which seems to allow 2 white continuations A and B. But a has a positive effect which prevents B from working and b has a positive effect which prevents A from working. 1…a 2.A!(B?), 1…b 2.B!(A?)
Durbar: All the moves of the mating side are made by the King.
Echo: A theme in which a mating configuration recurs on different parts of the board in separate variations. Echo is chameleon if the squares where the mated (stalemated) side King is are of different colours.
Excelsior: A pawn begins on its initial rank in the diagram, and proceeds to promote during the course of the solution.
Focal play: A theme in which a black line-piece (queen, rook, or bishop) “focuses” on two squares in different directions, and upon moving, is forced to “lose the focus” and unguard one of the squares.
Grimshaw: A theme in which two pieces of the same colour (usually a rook and a bishop) interfere with each other’s line of action, by playing in turn to a square where the two lines intersect.
Half-battery: An arrangement in which two pieces of the same colour stand between a friendly line-piece and the enemy king, so that moving either of the intermediate pieces off the line would produce a battery with the remaining piece.
Half-pin: A theme in which two black pieces stand on a line between the black king and a white line-piece, such that moving either black piece off the line leaves the remaining piece fully pinned. This pin is then exploited by White who gives a pin-mate.
Hannelius: in a twomover, the following pattern: 1.X?(2.A#)1...a!; 1.Y?(2.B#)1...b!; 1.Z!(~) 1...a 2.B#, 1...b 2.A#
Holst: A threat is defeated by a specific promotion of a black Pawn. The foreplan forces the promotion of this black Pawn to a different piece, so that the original defence is no longer available.
Indian: A unit makes a critical move in relation to a square where another same colour piece first intercepts it, and then reopens the line.
Kiss: in a twomover, the following pattern: 1.A? 1…x 2.B#, 1…y 2.C# / 1.B! 1…x 2.C#, 1…y 2.A#
Kniest: A side captures on the square where the opposite King will be mated.
Knight-wheel: A knight make all of its eight possible moves.
Lacny: in a twomover, the following pattern: 1.X? 1…a/b/c 2.A/B/C# / 1.Y! 1…a/b/c 2.B/C/A#
Le Grand: in a twomover, the following pattern: 1.X? (2.A#) 1…a 2.B# / 1.Y! (2.B#) 1…a 2.A#
Novotny: A theme in which White plays a piece to a square that intersects two black defensive lines, usually controlled by a rook and a bishop, so that when either captures the white piece, the other black piece’s line will remain closed.
Nietvelt: A black unit selfpins itself because the threat must unpin it by withdrawal. The selfpinning must be used thereafter.
Obstruction: A strategic effect in which a piece arrives on a square, and thereby prevents a friendly piece from occupying it.
Orthogonal-diagonal transformation (ODT): A theme framework mostly seen in helpmates, in which the strategic effects that take place on orthogonal lines in one phase are shown again in another, but changed to occur on diagonal lines, and vice versa.
Phenix: A piece is captured and then a promotion to the same kind of piece occurs.
Pickaninny: The 4 possible moves of a black Pawn from its game-array square.
Pin-mate: A mate that is dependent on the pin of a defending piece in order to be effective.
Reciprocal change: 1…a 2.A#, 1…b 2.B#/ 1…a 2.B#, 1…b 2.A#
Rukhlis: 1…a/b 2.A/B# // 1…a/b/c/d 2.C/D/A/B#
Square vacation: A strategic effect in which a piece departs from a square, and thereby enables a friendly piece to occupy it.
Sushkov: White's moves in at least 2 phases have positive effects in common which seem to allow at least 2 threats. However, each of these white moves contains a harmful effect which prevents all but one threat from working.
Switchback: A piece returns to a previously occupied square after it occupied only one other square.
Tempo play: A kind of waiting manoeuvre executed by a player who is already positioned correctly, serving no function other than to use up the extra time available.
Transferred mate: 1…a 2.A# / 1…b 2.A#
Turton: A piece A moves along a line across a square (critical square) allowing another piece B of the same colour to move to the critical square. Then, B moves on the line in the opposite direction, being supported by A. Turton: B is stronger than A. Brunner-Turton: A and B are of the same kind. Loyd-Turton: A is stronger than B. Zepler-Turton: After B has moved on the critical square, it is A that moves again on the line, being supported by B. Bicoloured Turton: The pieces are of different colours.
Umnov: White plays to the square which Black has just left. The theme is delayed if White doesn't play to that square immediatly.
Urania: 1.A? / 1.X?(2.A#) / 1.Y! (2.Z#) 1…x 2.A#
Valladao task: Promotion + Castling + En passant capture
Vladimirov: 1.A? 1…a! / 1.B? 1…b! / 1.X! 1…a 2.A#, 1…b 2.B#
Zabunov: The forward piece from one battery makes an ambush move and becomes the rear piece of a newly created battery.
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