Thursday, February 06, 2014

A very difficult brain challenge!

White to move and win :) No computer please!

Just to clarify the position, White has King on d6, Pawns on g3 and d7, Knight on f4, and Bishop on d1. Black has King on g7, Knight on a6 and g5, Bishop on b4, and Pawns on c3, d3, c5 and h6.


Andrija Djuranovic said...

D8Q-c4+; Kc6. The end.

Anonymous said...

Way too difficult.

SRB said...

Very difficult...been scratching my head for half an the hell can white win?

SRB said...

Very tricky...

Sagar said...

Slight correction to the co-ordinates the black pawn is not on d3, it's on e3 as per the picture.

s.k.srivastava said...

in photograph pawn is on e3

Sagar said...

I think i got the solution. Not 100% sure. After d8=Q, only option for black is to give checks to avoid queen from coming in. But either c4+ or Ne4+ are options. In both cases, white king can go safety with Kc6. After that black has no check option. Nb8+ will get taken by Queen. So black has to move king and Queen together with the knight on f3 should build a mating net and close out.

Anonymous said...

it's a bishop mate!

Inigo Atkin said...

Is the pawn intended to be on d3 or e3?!

Anonymous said...

I thinm Ive seen this before. I believe the story goes that someone showed it to a bunch of super gms at a tounament and tal was the only one to solve it

Soulful1 said...

Bb3 is my head hurts

SRG said...

I think it starts with 1.Ne6+ Kg62.Nxg5 Ba5 3.Ne6 e2 4.Bxe2 c2 5.Bd3+ Kh5 6.Bxc2 Nb8 7.d8=Q etc... ends as (Bishop,Knight,King Vs King)

davey said...

I thought I'd cracked it with:
1.Nh5+ Kg6 2.Bc2+ KxN 3.d8(Q) Nf7+ 4.Ke6 NxQ 5.Kf5 e2 6.Be4 e1(Q) 7.Bf3mate
but 6... e1(N)!

Ah, but then my chess computer was able to crack it from there with nifty shuffling of the bishop, which I'll leave to people to get. So, I half solved it, anyway! Although, half figuring things out when playing chess is no good.

Cortex said...

The challenge continues! This version of the study is sound and beautiful, so don't hesitate to try and solve it.

Full references after somebody posts the solution of this difficult but superb indeed study!

Anonymous' February 6, 2014 at 10:24:00 post is a serious hint.

davey said...

Ok, how about:

1.Nh5+ Kg6 2.Bc2+ KxN 3.d8(Q) Nf7+ 4.Ke6 NxQ 5.Kf5 e2 6.Be4 e1(N) 7.Bd5 c2 8.Bc4 c1(N) 9.Bb5 Nc6 10.BxN Nc7 11.Ba4 Ng3 12.Be1 Nf2 13.BxN any 14.BxN mate.

Cortex said...

You solved it very well, even if complicated minds will correct "Ng3 12.Be1 Nf2 13.BxN any 14.BxN mate." to "Nf3 12.Bd1 Ne2 13.BxN any 14.BxN mate." but who cares?

There are a few points to add in this post.

I) Chronology of the study

1) This is a version of study by Gijs Van Breukelen composed in the 1970's

2) Jim Plaskett, a strong IGM, showed it at a tournament in Brussels in 1987. Only Tal could manage to solve it.

Plaskett's version:

FEN: 8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

3) In 1990, Van Breukelen published this study with other versions in Schakend Nederland

4) In 2003, chessbase published the "Plaskett" version of this study in their puzzle section. Some analysts, including Alain Villeneuve, Roberto Balzan and Jim Plaskett (!) warned chessbase that 4...Kg4 was a bust, or, for Villeneuve, at least unclear.

Balzan suggested to add a white h2 pawn in the Plaskett version of the study.

4) In a dead chess website, Chessville, Daren Dillinger claimed also that this study was busted with 4...Kg4

5) This puzzle is a recap:
see (posted six years ago)

Apparently, the author itself saw the ...Kg4 flaw and has published other than this version


6N1/3P3k/n2K3p/2p3n1/1b6/2p1p1P1/8/3B4 w - - 0 1

other versions in 1990 that excluded any doubt after the sequence d8Q Kg4:

FEN: 8/3P3k/n2K3p/2p1n3/1b4N1/2p1p1P1/8/3B4 w - - 0 1

FEN: 4NB1k/3P4/n2K1p1p/2p1n3/1b6/2p1p1P1/8/3B4 w - - 0 1

which are more or less the same with/without an intro.

II) Summary

The Dillinger version and the Balzan version excluded again both the defense ...Kg4, which is not the case with the original, some Van Breukelen versions and the Polgar version.

III) The big surprise or "Coup de théâtre"


Even in the original setting (aka Plaskett setting), the Van Breukelen "flawed" version and the Polgar version, ...Kg4 doesn't bust the study!

IV) Demonstration:

In this position

FEN: 3Q4/8/n2K3p/2p3n1/1b4k1/2p1p1P1/2B5/8 w - - 0 5

we can, for a moment, switch on the engine who tells us that after the apparently best line for both sides

4... Kg4 5. Qf6 Kxg3 6. Qe5+ Kf3 7. Bd1+ Kg2 8. Qxe3 c4+ 9.
Kd5 Bc5 10. Qxc3 Bf2 11. Qf6 Nc5 12.Qxh6 black can't achieve a fortress. White wins, Von Breukelen's first setting and version, and of course Polgar's setting are both saved and sound.

But, as a puzzle, it is not as clear-cut as

FEN: 8/3P3k/n2K3p/2p1n3/1b4N1/2p1p1P1/8/3B4 w - - 0 1

which is won without a mind-wrenching analysis on a non-intuitive, unnatural but astonishingly hard-to-break black defense.

V) Consulted web sources:

-EG 122 from november 1996, downloadable thanks the great composer Gady Costeff
-Chessbase puzzle containing the original study mirrored (archive)
-Solution and discussion (archive)
-Dillinger's bust of the study and reconstruction (archive)
-The best research so far about this study in the net (in german)
-A video explaining this study
-Link to the first time this puzzle was posted in this blog

extra: explanation of the Forsythe-Edwards notation (FEN)

Thanks for reading!

Cortex said...

My last post was not very clear about one crucial detail:

in fact, the "Plaskett version" is very probably Van Breukelen's original version. The other configurations of pieces by the latter are either versions (better disposition of pieces) or corrections eliminating the near-bust Kg4 because of a checkmate in nine moves.

This is a wild guess of mine, because I am not a specialist, just a man fond of studies.

Van der Heijden, Winter or even Jim Plaskett himself could probably clarify this topic. The first two gentlemen are specialists in their field and have accumulated by the years a lot of documentation or contacts.

Is this an open question to solve?