Friday, February 2, 2024

Award of Crisan-50 JT

The announcement of the Crisan-50 JT was published in Quartz-56 (page 943).
The full uncensored award can be downloaded here.

Thursday, January 9, 2020

5 draw pendulums in Retractor

The draw pendulum is a retro specific element used in retractor problems. Based on the three fold repetition of the same position, White can force Black to retract a weak move instead of a strong move. In order to achieve this objective, the critical position must be obtained after Black’s retraction, then White can start the pendulum.

The draw pendulum theme fascinated many composers, who found several ways of expressing it, such as the short form (the so-called amputated draw pendulum), exploiting the losing of castling rights / en passant capture or zugzwang motivated. One major challenge was to show the theme in a five fold presentation – the topic of this post. (Definitions at the end of the article)

Michel Caillaud was the first composer to achieve 5 draw pendulums.
Let’s study together his magnificent composition (H25 from the FIDE Album 2013-2015):

Caillaud, Michel
2nd Prize, feenschach, 2015
In memoriam Milan Velimirović

-31 & #1Proca Retractor 10 + 10

Show Solution

Thursday, July 25, 2019

Changed mates after same defenses in three-movers

Changed mates have been considered one of the most exquisite artistic expressions in two-movers. The reader may find an excellent presentation of two-movers with changed mates in this OzProblem article by Peter Wong: Zagoruiko.

Naturally, chess composers tried to express this idea in longer problems as well. The first successful rendering of the idea dates back in the 19th century, when Stanislav Trčala published the following composition:

Trčala, Stanislav
Zlatá Praha 1897

#3 9 + 7

Show Solution

Here there are even three changed mates after Black defenses 1… Ke5 and 1… Kc5.
Of course, White continuations are checking and some mates are model, according to Bohemian school principles.
A slight blemish is the triple mate in the threat, although the quiet second move is highly enjoyable.

Sunday, January 25, 2015

Valladao theme in Proca Retractor

The Valladao task (thus named after Joaquim Valladão Monteiro) is a mix of the three special moves: castling, en passant capture and [minor] promotion, in a single chess problem. Naturally, this blend has attracted many chess composers and the retro genre makes no exception.

In the selected four Proca Retractor compositions the thematic moves appear in the retro play. Interested readers may find other examples in which the castling or the promotion appear in the forward play. (To find them, go to PDB website and search "k='valladao' and stip='proca'")
As usual in Proca Retractors, the main challenge is to ensure there are no duals in the retro or forward play.

The below 1st Prize winner would demonstrate many specific points:

Wenda, Klaus
König & Turm, 2003 (U252)
1st Prize

-11 & #1AntiCirce Calvet
Proca Retractor
No Forward Defense
5 + 6

Show Solution

Walter, Martin
Die Schwalbe, 2006 (13185)

-6 & #1AntiCirce
Proca Retractor
6 + 7

Show Solution

More difficult is to show the retraction of the white castling. The only convincing example so far has been realized by the regretted German expert Wolfgang Dittmann and it is also the first one to show the s#1 stipulation in the forward play.

Dittmann, Wolfgang
Die Schwalbe, Aug 2002 (11589)
2nd Comm.

-4 & s#1AntiCirce
Proca Retractor
6 + 9

Show Solution

The above examples showed Valladao using AntiCirce. It is also possible to mix Proca Retractor with other fairy conditions, as in the next example.

Crişan, Vlaicu
Die Schwalbe, Apr 2013 (260/15553)

-7 & s#1CirceAssassin
Proca Retractor
11 + 5

Show Solution


Proca Retractor definition:
A Proca Retractor is a defensive Retractor. Black is defending by trying to retract the moves that will forbid (or delay) the achievement of White's goal. You may see at the Retro Corner an example by W. Dittmann of orthodox Proca Retractor showing two en passant captures.

Anticirce: the capturing piece disappears and is immediately reborn on its home square while the captured piece is removed for good. The capture is not legal if the rebirth square is not free. A pawn capturing on the eighth rank is first promoted and then reborn on the home square of the promoted man. Here "checks are fairy" i.e. a King is not in check if its "capture" is not legal because the rebirth is not possible.
In AntiCirce Cheylan a piece is not allowed to capture on its home square; in AntiCirce Calvet this is allowed.

Circe Assassin: the captured unit is reborn on its rebirth square even if the rebirth square is occupied. And then the occupying unit disappears for good. Hence a unit on its home square cannot be removed.

Wednesday, December 18, 2013

White & Black double en passant capture in Proca Retractor

The en passant capture is, together with castling and promotion, one of the three special moves in chess. The special character of the en passant capture is underlined by the fact that the arrival square is not occupied by the captured piece – an effect which can be also met in fairy chess compositions.

In Proca Retractor compositions the main challenge is to find good motivations in order to force Black to retract the en passant capture. This challenging theme can be realized combined with different fairy conditions.

Proca Retractor definition:
A Proca Retractor is a defensive Retractor. Black is defending by trying to retract the moves that will forbid (or delay) the achievement of White's goal. You may see at the Retro Corner an example by W. Dittmann of orthodox Proca Retractor showing two en passant captures.

The first composer who successfully showed the Black and White double en passant capture was Dr. Klaus Wenda. In the first two problems we can see how he managed to present this theme combined with Madrasi and AntiCirce Cheylan.

Sunday, April 28, 2013

A lucky piece arrangement?

This post is dedicated to an interesting piece arrangement involving white King, Rook, Bishop and Knight(s) and black King in helpmate in 3.

Five years ago, with the occasion of the Chess Olympiad in Dresden 2008, a quick composing tourney with two sections was organized. The required theme in the tourney was:
In a h#3 White pins (after a checkless key) his own piece on its first move. The pinned piece delivers check mate.

Crişan, Vlaicu
Dresden Olympiads, 2008
1st Prize

h#3b) wSe6->c5
5 + 10

Show Solution
The judge Udo Degener praised the construction hoping that no anticipation will be found. The whole play is based on the destruction of two black batteries unpinning the thematic white pieces and black Grimshaw.
The black Queen performs a selfblock while unguarding the mating square.

[Award of the Dresden 2008 QCT]

One year later, the same piece arrangement leaded to another success in a different tournament:

Friday, January 11, 2013

Loshinsky 100 - about a "Loshinsky-magnet" problem

On the occasion of Lev Loshinsky's coming centenary (Jan.17th), it may be profitable and instructive to return to a problem by Lev Loshinsky which was mentioned on this blog. In fact, the problem quoted there was a version of Lev Loshinsky's magnet masterpiece.

In 1947, Loshinsky published his first prizewinner showing the magnet theme: