A puzzle of sorts

@greenpawn34 said
Hi Eladar,

Don't know If I am anywhere near close. Opening post indicates it is deep.
I just look for forcing moves, checks, pawn and piece sacs and go from there.
The clues hints it is not a tactical two move trick.

Yes Geoff , it is deep.
The "answer" move for white is move 29.
The checkmate at the end is move 37!!
Another example variation goes up to move 34 where it says "white's attack is decisive".
This stuff is way beyond me but I'm pleased so many of you have had a look.
Let me know when you want the answer and I'll post the rest of the blurb from the paper.
I hope I'm not infringing any copywrite laws!!

b5 is not forced and forcing. Black can play Bc5 then Nxf2 with Nxh3 to follow. This is very much a computer puzzle because if you need stockfish to find the position eventually then humans would not enter into this situation.

It's like hearing a guy in the chess club saying position 13 in the razor or knives variation is winning without seeing how or what they are talking about.

Razor and knives are made up to illustrate my point. 🙂

A bit more background:-
The chap who was asked to find the next move was David Howell who I believe is a grandmaster.
The game was between Nils Grandelius and Simen Agdestein,Nordic online league lichess.org 2020 .
I daresay if you use Lichess you may be able to find it.
I can't post a pgn of the game because I don't know how the game reached the position shown so when I give the answer it'll have to be notation only which obviously means you will need a board to follow the moves.
Thing is, if someone does find it, it won't give the answer to the question because the move actually made in the game led to a draw!!
The "magic" move was only found afterwards as I said at the start(by Stockfish eventually and by one of the players after analysing with a computer)

As soon as you mentioned winning move i thought of the Queen (Qh3) after making space for the Queen via bishop move but Bd7 can mean black just takes the piece with some compensation. So clearly if white can move the bishop somewhere forcing then the Queen is on the way.

Found the solution online (and this Bishop move is actually forcing Greenpawn).

29 Be6! leads to a winning position for White. In human terms, this sacrifice allows White to activate his queen via h3. For engines, it is possible to calculate that Black’s kingside lacks sufficient defenders. I re-commend readers to analyse this fascinating position on aboard. Some sample variations:29…fxe6 30 Qh3 Bf6 (30…Rd6 is tenacious but White’s attack rages on: 31 Bxg7! Kxg7 32 Qg4+Kh8 33 Ne5 Rg8 34 Qh5 Qf8 35 Rxe7! is a nice line: 35…Qxe7 36 Qxh6+ Qh7 37 Nf7 mate) 31 Qh5! Re7 32 Rxe7 Bxe7 33 Bxg7! Kxg7 34 Ne5 and White’s attack is decisive. It’s worth noting that the black queen is misplaced and ineffective. Stockfish finds 29 Be6! after some thought.

@congruent said
b5 is not forced and forcing. Black can play Bc5 then Nxf2 with Nxh3 to follow.

1.b5 Bc5 gives White the option of getting two Bishops for a RooK. 2.Rxc5 and 3. bxa6.

But that is an option, I'd loathe to take that Rook off the 7th unless I had to.

So not Rxc5. Stay with Plan A , the a8 Queen. 1 b5 Bc5 2.Ra1 that awkward
Black Queen is critical. 2...Nxf2 3.Rxa6 Nxh3+ 4.Kg2 White is winning.

Looks like 1.b5 is forcing and cannot be ignored after all and I can still recognise
one. (and I even did it without having to go hunting online to find another one 😉 )

So 1.Be6 is the computer move. Never looked at it. As I said once hooked
on the bad Black Queen I went fishing in there even though I knew from the
opening post it would be probably be wrong, unless there was triple !!! follow up.

I approached these puzzles as I always do...What would I play? I would have
played 1.b5 Black has to take it. Looks OK and if it tempts out a human mistake
like 1...Bc5 then job done.

@congruent said
As soon as you mentioned winning move i thought of the Queen (Qh3) after making space for the Queen via bishop move but Bd7 can mean black just takes the piece with some compensation. So clearly if white can move the bishop somewhere forcing then the Queen is on the way.

Found the solution online (and this Bishop move is actually forcing Greenpawn).

29 Be6! le ...[text shortened]... oting that the black queen is misplaced and ineffective. Stockfish finds 29 Be6! after some thought.

That is exactly what it says in the paper.
It would appear that everything is "online" these days.
Google has ruined pub quizzes because of mobile phones and it would seem chess puzzles will go the same way.
Progress?

@venda

Sorry your thunder was stolen! Was that the Yorkshire Post's saturday chess column? I've found that quite good although I don't buy it every week.

Here's the mate variation.

@Ragwort
Actually it was the Saturday times chess column but it only showed the game from the position I posted in the fen.
Presumably the" Post "showed the whole game which is how you managed to post the pgn.
Unless there's another way?
In any case, many thanks for the post and the interest

@venda

No, I hadn't seen this before you posted it. I made the pgn start from your fen and put the moves in by hand from congruent's post.
fen is based on the old forsyth notation for a position from the days before computers; starting at a8 - and you can start a pgn sequence from a fen. RHP's version is quirky like needing a full stop and a space after each move number and no line feeds so copying pgn from elsewhere can be frustrating but short sequences by hand are ok.

@venda said
There was an interesting "puzzle" in my newspaper this weekend.
It's from an actual game and the question is "white's best move" so it's not a "checkmate in n" type puzzle I could put in the puzzle section.
Apparently Stockfish found the "best move"eventually and a human came up with the same answer after several hours of analysing with the help of a computer!!.
I think some ...[text shortened]... the temptation
Here goes:-
[fen]q2rr1k1/2R1bpp1/bp5p/3pB3/1P2n3/5NPB/4PP1P/3R1QK1 w - - 0 1 [/fen]

All I can think of is getting the major pieces on better squares. Rdc1 connecting the rooks and Qe1 making e3 possible. I'm sure these are not "the best" but this one is a bit beyond my horizon. 🙂

@ragwort said
@venda

No, I hadn't seen this before you posted it. I made the pgn start from your fen and put the moves in by hand from congruent's post.
fen is based on the old forsyth notation for a position from the days before computers; starting at a8 - and you can start a pgn sequence from a fen. RHP's version is quirky like needing a full stop and a space after each move number ...[text shortened]... d no line feeds so copying pgn from elsewhere can be frustrating but short sequences by hand are ok.

" and you can start a pgn sequence from a fen. "
Interesting. I didn't know you could do that.
I thought you had to post the entire pgn(like in the example shown in FAQ) and then delete the bits you didn't want.
When you have the time, I'd appreciate an example/explanation in a pm of how you did it.
Thanks and no rush

[pgn]
[fen "q2rr1k1/2R1bpp1/bp5p/3pB3/1P2n3/5NPB/4PP1P/3R1QK1 w - - 0 1"]
1. Be6 fxe6 2. Qh3 Rd6 3. Bxg7 Kxg7 4. Qg4 Kh8 5. Ne5 Rg8 6. Qh5 Qf8 7. Rxe7 Qxe7 8. Qxh6 Qh7 9. Nf7 [/pgn]

That's difficult to do in a pm because it recognizes the code and tries to put the board and pgn in the message. I have edited my post to show just what I typed to make the pgn start from your fen. Basically you put the begin pgn marker at the start, then then fen code contained within speech marks and marked fen within square brackets then the moves then the end pgn marker to finish.

@ragwort said
@venda

No, I hadn't seen this before you posted it. I made the pgn start from your fen and put the moves in by hand from congruent's post.
fen is based on the old forsyth notation for a position from the days before computers; starting at a8 - and you can start a pgn sequence from a fen. RHP's version is quirky like needing a full stop and a space after each move number ...[text shortened]... d no line feeds so copying pgn from elsewhere can be frustrating but short sequences by hand are ok.

I find this board easy to use from fen.

https://www.apronus.com/chess/pgnviewer/

@ragwort said
That's difficult to do in a pm because it recognizes the code and tries to put the board and pgn in the message. I have edited my post to show just what I typed to make the pgn start from your fen. Basically you put the begin pgn marker at the start, then then fen code contained within speech marks and marked fen within square brackets then the moves then the end pgn marker to finish.

Thanks for going to all the trouble my friend.
I'll save your message and I might try something sometime when I have anything interesting to post

@eladar said
I find this board easy to use from fen.

https://www.apronus.com/chess/pgnviewer/

Thanks Eladar.
I've had a quick look and it looks easy to use