Month: March 2021

reciprocal play

In two variations or phases, there may be a mutual exchange of elements such as mates, moves, sequences of moves, functions of the pieces, motifs of moves, etc., which can be expressed using the AB-BA scheme.

reciprocal moves

In two phases or variations, one side makes the same moves in the different order.

reciprocal dual avoidance

Mutual dual avoidance which occurs when white has the same apparent pair of mates (or continuations) present in two variations.

reciprocal defensive motifs

In two phases, black’s two defenses switches their defensive motifs.
W dwóch fazach dwie obrony czarnych zamieniają wzajemnie motywy obronne.

Wróbel, Marian
Polski Związek Problemistów, 1948
1st Prize
FIDE Album 1945-55

mate in 3 moves

Hannelius theme

The first try, with the threat “A”, is refuted by the “a” move. The second try with the threat “B” is refuted by the move “b”. In the next phase, usually the solution, a defence “a” is followed by mate “B” and mate “A” after “b”.

Scheme of the theme:
1.X? ~ 2.A, 1…a!
1.Y? ~ 2.B, 1…b!
1.Z a 2.B, 1…b 2.A

ideal Hannelius

The Hannelius theme where in the first try there is a defense “b” followed by mate “C” and in the second try there is a defense “a” followed by mate “D”.

Scheme of the theme:
1.X? ~ 2.A, 1…b 2.C, 1…a!
1.Y? ~ 2.B, 1…a 2.D, 1…b!
1.Z a 2.B, 1…b 2.A

cyclic Hannelius

Scheme of the theme:
1.X? ~ 2.A, 1…a!
1.Y? ~ 2.B, 1…b!
1.Z? ~ 2.C, 1…c!
1.K a 2.B, 1…b 2.C, 1…c 2.A

defence-based Hannelius

Scheme of the theme:
1.X ~ 2.A, 1…a 2.C
1.Y ~ 2.B, 1…b 2.D
1.Z a 2.B, 1…b 2.A

Chepizhny, Victor
Memorial D.Kanonik, Chervony girnik, 1992-93
2nd Prize
FIDE Album 1992-94

mate in 2 moves

Knight wheel

Black Knight plays on all eight fields available to him.

Petrovic, Nenad
Chess, 1946
Special Prize
FIDE Album 1945-55

mate in 2 moves