Chess Puzzle: Extraordinary Solution

[Dynasty]

Here's a prize winning chess puzzle. This position did not occur in an actual game. It was created as part of a contest.

It's White's move. The goal is to find a forced combination which leads to White checkmating Black.

http://img.photobucket.com/albums/v720/DynastyPoker/puz7a.jpg

["spaceman"Bryce]

a7-b8?

[slickpoppa]

what kind of an idiot promoted a pawn into a bishop /images/graemlins/ooo.gif

[Dynasty]

[ QUOTE ]
a7-b8?

[/ QUOTE ]

The correct answer will only be one which provides the entire line. You can't get credit simply for providing the first move.

However, that can be a good way to get a discussion rolling.

[theBruiser500]

[ QUOTE ]
what kind of an idiot promoted a pawn into a bishop /images/graemlins/ooo.gif

[/ QUOTE ]

chess puzzle makers like to make up weird situations where you do all sorts of wacky stuff

["spaceman"Bryce]

I wont be able to figure out the whole thing because i am retarded-Bryce

[mostsmooth]

about how many moves we talkin here?

[TimM]

[ QUOTE ]
a7-b8?

[/ QUOTE ]

This just loses outright.

I won't comment further as I've seen this one.

[Popinjay]

im pretty sure the whole key to this for black is maintaining control of the f3 square and not moving his king. if he loses f3 white can check him with his bishop and move his king. then the white king can move forward and soon queen a pawn-leading to checkmate. so i think you have to figure out all the tempos so that the black c and d pawns dont screw you up (the other pawns are all blocked or will be at a certain point). waste tempos with the trapped bishop.

i could be missing something important here but that looks to me how it goes.

[Dynasty]

[ QUOTE ]
[ QUOTE ]
a7-b8?

[/ QUOTE ]

This just loses outright.

I won't comment further as I've seen this one.

[/ QUOTE ]

Just to help out, 1. Bb8 loses because Black can actually play 1...Kxb8. White isn't threatening 2. Ka6 (to push the b6 pawn) because Black has 2...d3 which will Queen a pawn and give Black the win.

[GrekeHaus]

[ QUOTE ]
I wont be able to figure out the whole thing because i am retarded-Greke

[/ QUOTE ]

["spaceman"Bryce]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
a7-b8?

[/ QUOTE ]

This just loses outright.

I won't comment further as I've seen this one.

[/ QUOTE ]

Just to help out, 1. Bb8 loses because Black can actually play 1...Kxb8. White isn't threatening 2. Ka6 (to push the b6 pawn) because Black has 2...d3 which will Queen a pawn and give Black the win.

[/ QUOTE ]
So losing a bishop isnt the best way to proceed??

["spaceman"Bryce]

what happens if you take like 8 moves with the king to un cornerize him.

["spaceman"Bryce]

[ QUOTE ]
what happens if you take like 8 moves with the king to un cornerize him.

[/ QUOTE ]
never mind that suburban king is trapped no matter what

[TStoneMBD]

im probably wrong, but i disagree. i cant think this far ahead and i dont have any poker software on my computer, but it seems;

a7-b8 b7-b8
a5-a6 d4-d3
a2-b1 d3-c2
b1-c2 f6-f5
b6-b7 f5-f4
b5-b6 h5-h4


you then move you c2-e4

you bring your king all the way to the bottom of the board while black slowly moves his pawns, then you start plucking pawns off 1 by 1 along with the knight until the only piece on blacks side is the king which cannot move.

does this not work?

[Shillx]

[ QUOTE ]
im pretty sure the whole key to this for black is maintaining control of the f3 square and not moving his king. if he loses f3 white can check him with his bishop and move his king. then the white king can move forward and soon queen a pawn-leading to checkmate. so i think you have to figure out all the tempos so that the black c and d pawns dont screw you up (the other pawns are all blocked or will be at a certain point). waste tempos with the trapped bishop.

i could be missing something important here but that looks to me how it goes.

[/ QUOTE ]

Yeah I was thinking about pushing the white C2 pawn up and in two moves we would force the black pawn to either take our pawn (and open up the king) or let him go by and get a queen.

Brad

[TimM]

[ QUOTE ]
So losing a bishop isnt the best way to proceed??

[/ QUOTE ]

No. Actually I think OOT should be able to solve this one. There just aren't that many legal moves to choose from on each move. You have two moves that don't lose a bishop, is there a reason you have to choose one over the other?

["spaceman"Bryce]

lets see a-1 to b-2 then a7 b8? then a5-a6 then push pawn forward? eh i shouldnt be posting on chess...

[mostsmooth]

Ba2-b1 back and forth until all black pawns are moved down and blocked by the h bishop and their own f pawn.B ends up on B1
black will have to move d pawn, white takes.
now black has to move c pawn, white takes with B.
black must move K or N. at this point i dont know the best move for black, but id say to move the K, which leads to white K moving to A6, leading to promotion and mate. i cant do the rest in my head , so this is my submission. be gentle
/images/graemlins/cool.gif

[TimM]

[ QUOTE ]
im probably wrong, but i disagree. i cant think this far ahead and i dont have any poker software on my computer, but it seems;

a7-b8 b7-b8
a5-a6 d4-d3
a2-b1 d3-c2

[/ QUOTE ]

He has d3-d2 here and queening next.

[Popinjay]

okay the first move has to be Bb1

[TStoneMBD]

i read most of your paragraph. looks right.

excellente.

[Stuey]

Chess Board Setup
Every chessboard is made up of eight rows and eight columns in alternating colors, for a total of 64 squares. To complete the chess board setup, you should position the board so that a white square is on the extreme lower right hand side of the chess board (as you can see, this works for both players).

The illustration below shows how the pieces should be setup on your chessboard. When you find out how all the pieces move you will notice that the front rank is fully initially supported by the rank behind.

When doing a chess board setup, make sure that the white queen is positioned on a white square and the black queen is situated on a black square. The two armies should be mirror images of one another.

The white side always moves first. Each player's side of the chessboard is determined by chance. Usually by one player placing a pawn in each hand and closing his fists. Holding forth his fists the opposing player picks one. Whatever color the pawn he chooses is the side he shall command.

Which direction is white/black headed? /images/graemlins/tongue.gif

[soah]

I suck at chess, but the solution I see is to move back and forth from A2 to B1 until black runs out of safe places to move his pawns. Eventually he must move his knight, and then the game is over in a couple turns. That's too easy to actually be the correct answer, though.

[Dynasty]

[ QUOTE ]
Ba2-b1 back and forth until all black pawns are moved down and blocked by the h bishop and their own f

[/ QUOTE ]

That won't work. After..

1. Bb1 h6 (or another pawn move)
2. Ba2 d3!

Black will now Queen a pawn. White is unable to prevent it.

You can not simply move the bishop back and forth. Black's threat of ...d3 prevents this.

[mostsmooth]

[ QUOTE ]
[ QUOTE ]
Ba2-b1 back and forth until all black pawns are moved down and blocked by the h bishop and their own f

[/ QUOTE ]

That won't work. After..

1. Bb1 h6 (or another pawn move)
2. Ba2 d3!

Black will now Queen a pawn. White is unable to prevent it.

You can not simply move the bishop back and forth. Black's threat of ...d3 prevents this.

[/ QUOTE ]
ok then, how about once the B is on B1 we keep it there and then we move the K up and down to kill time?

[Dynasty]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
Ba2-b1 back and forth until all black pawns are moved down and blocked by the h bishop and their own f

[/ QUOTE ]

That won't work. After..

1. Bb1 h6 (or another pawn move)
2. Ba2 d3!

Black will now Queen a pawn. White is unable to prevent it.

You can not simply move the bishop back and forth. Black's threat of ...d3 prevents this.

[/ QUOTE ]
ok then, how about once the B is on B1 we keep it there and then we move the K up and down to kill time?

[/ QUOTE ]

So,

1. Bb1 h6 (or other pawn move)
2. Ka4 Ka8

If White moves his King away from the a6 square, that frees Black's King to move as well because White no long threatens Ka6 followed by b7. Black won't have to move his pawns. He can play his King back and forth between the a8 and b7 squares.

I'm not trying to squash any ideas you've got. I'm simply giving you Black's best alternatives to your moves so that you can refine White's plan.

[Popinjay]

Now I'm thinking you have to let him queen his c or d pawn to free your bishop. Looks like there could be a forced mate if that bishop gets free even if he does queen.

[mostsmooth]

does it have anything to do with moving the king down to A1, then the B to A2, then walking the K across the bottom?
if not i give up
i was trying to find a way to make an odd number of moves to force the black king away, but im tired

[Dynasty]

[ QUOTE ]
does it have anything to do with moving the king down to A1, then the B to A2, then walking the K across the bottom?
if not i give up
i was trying to find a way to make an odd number of moves to force the black king away, but im tired

[/ QUOTE ]

1. Bb1 h6 (or other pawn move)
2. Ka4 Ka8
3. Ka3 Kb7 (Black just moves his King back and forth)
4. Ka2 Ka8
5. Ka1 Kb7
6. Ba2 Ka8 (White's King can now stop the threat of ...d3)
7. Kb1 Kb7
8. Kc1 Ka8
9. Kd1 Kb7
10. Ke1 Ka8
11. Bb1 Kb7 (White must move the bishop to b1 to stop d3 before proceeding)
12. Kf1 Ka8
13. Kf2 Kb7
14. Ke1 Ka8

The last three moves by White are the key. He is "triagulating". He moves his King three times but ends up on the same square (e1) that he started on. Meanwhile, Black has moved his King three times but is on a different square from where he started. White has wasted a tempo and can now take advantage of a position which is now slightly different.

15. Kd1 Kb7
16. Kc1 Ka8
17. Ba2 Kb7
18. Kb1 Ka8
19. Ka1 Kb7
20. Bb1 Ka8
21. Ka2 Kb7
22. Ka3 Ka8
23. Ka4 Kh7
24. Ka5

By using the triangulating tactic, White has achieved a position where his King is again on the a5 sqare. But, instead of it being White's move, it is now Black's move. So, Black can't continue to move his King back and forth between the b7 and a8 squares. Black must move a pawn. So,

24...f5 (or some other pawn move by Black.

After that, White uses the same triangulation tactic over and over until Black has run out of pawn moves.

You can watch the complete solution here. Checkmate is forced...in 271 moves.

http://www.chessbase.com/puzzle/games/puz7.htm

[mostsmooth]

yeah, i wouldnt have figured out 271 moves

[JaBlue]

here's my guess:

1. Bb1 h4
2. Ka4 h3
3. Ka5 h2
4. Ka4 h5
5. Ka5 h4
6. Ka4 h3
7. ka5 f5
8. Ka4 f4
9. Ka5 f5
10. Ka4 Kc8
11. Ka5 f2
12. b7 Kd7
13. b8=Q f1=Q
14. Qb7 Ke6
15. Qc8 Nd7
16. Bc6 + - (white wins soon)

no computer or chess board used

[GrekeHaus]

I just discovered a way to do it in 270. You're all retards.

[mostsmooth]

[ QUOTE ]
here's my guess:

1. Bb1 h4
2. Ka4 h3
3. Ka5 h2
4. Ka4 h5
5. Ka5 h4
6. Ka4 h3
7. ka5 f5
8. Ka4 f4
9. Ka5 f5
10. Ka4 Kc8
11. Ka5 f2
12. b7 Kd7
13. b8=Q f1=Q
14. Qb7 Ke6
15. Qc8 Nd7
16. Bc6 + - (white wins soon)

no computer or chess board used

[/ QUOTE ]
how did you type all that without a computer? and how did you post it here? im gonna bet a computer was involved somehow.

[JaBlue]

how did I type it? With my hands. this type of calculation is very simple because the moves are forced. I think my answer is wrong anyway.

like i said, i didn't use a computer

[GrekeHaus]

Seriously though...that is pretty cool.

[Felix_Nietsche]

Blacks Options are limited:
*The pawns in column H are impotent while white's bishop occupies H1
*The pawns in column F are impotent while white's bishop occupies H1 and while black's King occupies the white diagonal that is threatened by the white bishop in H1.
*The black king is the only piece that can prevent white from promoted pawns to queens so it MUST guard column B at all costs.
*Black Pawn in column D could move but white bishop A2 to B1 screws that plan.
*Black pawn C2 is stuck
*Black knight can not move until black pawn F3 has moved forward. But doing so will be illegal unless black's King leaves that white diagonal. If the black king moves white has easy counter strategies....

White's strategy should be:
1. Too move its King from A5 to F2 and then to start attacking blacks pawns in columns F and H.
2. Take all the even exchanges that black gives.
Yes....it is a long trip. Once these pawns are dead white can promote a pawn to a Queen and black can NOT stop white from winning...
3. White's first move should be to move the bishop to B1.

Of course black may try some countermoves to stop this tactic.
Black Counter moves and white's responses"
a. Black: King to A8, White = Do nothing and keep moving the King.
b. Black: King to C8, White = P to B6(check), KxP(B6), white bishop takes black pawn(D4)...Now black is really f***ed.
c. Black: P to D3, White: Bishop to B2, PxP, BxP(C2)

Black can not stop the white King from escaping and eventually wiped out all its pawns on F and H without allowing white to promote a pawn to a Queen.

This seems too easy... Am I missing something? Perhaps this is not the most elegant way to solve this problem but I see no way that black can stop it....

[Felix_Nietsche]

/images/graemlins/frown.gif

[Skipbidder]

We need to find a way to waste moves as white, in order to force black to make pawn moves.

Start with Ba2-b1. Black has to make a pawn move now, because a king moves allows Ka6. Notice this situation, it is going to come up a bunch more times, as we tempo black into having to make pawn moves. d3 is no good now because out bishop is on b1, the f3 pawn is pinned. The knight has to protect that pawn, thus black forced to moved one of f6-f5, h5-h4, or h7-h6. In order to waste moves, we need to use the king. We can't waste moves with the bishop, since we have to protect against d4-d3. Now we start to move the king...we are going to end up on e1. This is going to take a while. I might be missing an easier solution, but I'm going to get there. Black can now afford to move his king to c8. That frees the f3 pawn from the pin, but doesn't really allow it to be moved, since b6-b7 will follow, with queening on the next move. Now we just move the king down to a1, while black shuffles his king between c8 (or a8, I suppose) and b7. (Black can move pawns instead, but this is going to make my job easier, so I'll assume he doesn't.) Now I'm going to make room for the king to slide under by playing Bb1-a2. Black doesn't benefit from d3 now because our king can stop the queening threat. We'll slip under to e1 now. We need to put the bishop back on b1 somewhere along the way. After we get the king to e1 will be fine. We need to put the bishop back on b1 because we are going to be moving our king to f2 along the way, when we wouldn't have time to defend against d4-d3. From King on e1, we are going to move Kf2, then Kf1, then Ke1. This will tempo black into having to either move a pawn (which will quicken his demise) or ending up allowing us to march our king all the way back to a5 when black is on b7 (and our bishop is on b1). This will force black to move one of his four free pawns. After the pawn move, we repeat the trip to e1. Lather, rinse, repeat. There are 11 total free pawn moves for black. (Well, only 10 left, since he had to move one right away). After all of these gyrations, we will be left with a position with black: Kb7, Ne5, pawns c3, d4, f3, f4, f5, h2, h3. White's pieces are all in their original squares, except that bishop is on b1. With black now to move, he is forced to play Kc8. (Ka8 is legal, but ends the game quickly after Ka6, any, c6-c7.) So, Kc8, Ka6, Kd8 or Kd7. Now b6-b7. To stop us from queening, black has to play Nd7. This allows us to gobble the f3 pawn. Whoops, I guess black had to play Kd8 only, not Kd7. Black can now dork around a while longer by sacrificing his pawns, but he can't do anything useful. We are going to queen, forcing black to capture with his knight (which we will take with our bishop). We will eventually be able to queen another b-pawn. Black has choices as to when he wants to sacrifice his pawns. That should just about do it. I estimate somewhere between 300 and 350 moves. I don't understand why the composer started a black pawn on h5 instead of h6. It looks like a legal starting position with it the other way, and it would cause the solution to be longer, which is what it appears that the composer was trying for. It takes one capture to get from g-file to h-file, one capture to get from e7 to f6, and 4 total captures to get the other pawns legally where they are at. Oh well, I'm through with this problem. Thanks, Skip.

[Skipbidder]

Damn it. I guess I have to type faster. I can't believe I spent so long on a chess problem when I have an Empire bonus to clear.

[bernie]

Im not a chess guy by any means but I have a question. Why can't the black, while white is on it's little journey, move more pawns? Effectively getting to the same point sooner? Obviously the 1 pawn is staying there for awhile protecting the Bking, but couldn't the others move sooner?

Could that have helped the black win? Or is it once the black is in this position, he's doomed to lose?

b

[Skipbidder]

Black doesn't want to move his pawns. He doesn't want to move at all. He can't make any useful pawn moves (the threat of moving the d4 pawn is always countered by either the position of the white king or the bishop on b1. The most advanced pawn on the f file is either pinned against the king (can't move because it would put the king in check) or allows the pawn to move (with check) and then queen. Only four black pawns can move, and they can't do anything useful. The point of all the white moves is actually to get black to move those pawns. If he does so sooner, then the mate will happen sooner. Every time that black moves a pawn, white runs back to e1 in order to use the f2-f1-e1 stall.

[bernie]

[ QUOTE ]
Black doesn't want to move his pawns. He doesn't want to move at all. He can't make any useful pawn moves (the threat of moving the d4 pawn is always countered by either the position of the white king or the bishop on b1. The most advanced pawn on the f file is either pinned against the king (can't move because it would put the king in check) or allows the pawn to move (with check) and then queen. Only four black pawns can move, and they can't do anything useful. The point of all the white moves is actually to get black to move those pawns. If he does so sooner, then the mate will happen sooner.

[/ QUOTE ]

So basically, from this point on, the black is drawing dead if white chooses to play it this way?

As I said, Im not really into chess, but it's a very interesting situation.

b

[Dynasty]

[ QUOTE ]

So basically, from this point on, the black is drawing dead if white chooses to play it this way?

[/ QUOTE ]

In poker terms, Black is drawing dead.

In chess terms, White has a forced mate.

When Black plays the best possible move each time, the checkmate takes 271 moves. If Black played any different than in the linked solution, the checkmate would occur faster.

[bernie]

Seems the key move was the white getting into this position. Would this likely have been planned a few moves prior?

b

[Bill Murphy]

I haven't read any of the replies in this thread yet, so maybe these have been covered. I'm also likely not using the word "meta" correctly. Anyway, I'm sure this puzzle was inspired by Smullyan's two chess books, which are well worth looking for.

1. Is this position possible to arrive at(however unlikely) under the normal rules of chess?

2. Assuming this is a possible position, is it also possible to determine:

a. What Black's last move was?
b. Which of the light-squared White bishops is the promoted one?
c. If the pawn on b3 came from a2 or b2?

http://img.photobucket.com/albums/v720/DynastyPoker/puz7a.jpg

[TimM]

I don't see anything that would make this position impossible. If I am really bored tomorrow I might try to compose a game that would lead to it.

[ QUOTE ]
a. What Black's last move was?

[/ QUOTE ]

No, I see at least 15 possible moves black could have just made, and that doesnt count that almost any of them could have been captures of 4 or 5 different types of piece.

[ QUOTE ]
b. Which of the light-squared White bishops is the promoted one?

[/ QUOTE ]

No. However the bishops got where they are, it would have been easy to switch them first.

[ QUOTE ]
c. If the pawn on b3 came from a2 or b2?

[/ QUOTE ]

It had to be from b2 or the B on a2 couldn't have got there.

[DCJ311]

AFter looking at this for maybe 2 minutes, my vote would be to play 1. Bb1 then follow up with a plan of Ka4-a3-a2-a1, Ba2, Kb1-c1 etc.

If at any point Black plays Kc8, I immediately play b7+ followed by Bxd4, with an easy win.

I can find no constructive plan for Black, as the pawn cannot be moved to f2 at any point, the d3 pawn sacrifice will not work if the bishop is on b1, and moving the pawns on h5 and f5 will not make any progress for Black, and White can simply begin to bring his King over to the other side of the board to gobble up the pawns.

So what am I missing?

[waffle]

WOW. I am amazed! I went through the replay and watched and read until I understood the reason for the triangulation. This is really neat. As only a casual chess player, my only problem is understanding why .. Ka8, .. Kb7, .. Ka8, .. Kb7 is optimal when the white king is not immediately threatening Ka6!

Oh, wait, I am starting to see some of this. Black can't .. d3 when white leaves c2 unguarded by the bishop and the king because .. Nxd3?? is not an option.

Very cool puzzle!

[Chris_P]

hmmm....
White Black
Ba7-B8 Kb7xB8
B6-B7 Kb8xb7
B5-B6

(your king is now free to release ur 2nd pawn on row c and get both of your bishops into play and with an advantage of 2 major pieces and 4 pawns to 1 major piece and 7 pawns with an isolated king)

correct?

[Cyrus]

[ QUOTE ]
Meta-Puzzles for Raymond Smullyan Fans. I'm likely not using the word "meta" correctly.

[/ QUOTE ]
Yeah, I believe that a meta-puzzle indicates a puzzle about a puzzle, just as meta-analysis indicates an analysis of analyses.

I happen to have a Smullyan book of retro-analysis, the one with Sherlock Holmes as the protagonist, and it is indeed very enjoyable! Link (http://www.amazon.com/exec/obidos/ASIN/0812923898/qid=1113311014/sr=2-1/ref=pd_bbs_b_2_1/002-9517445-9095257)

[ QUOTE ]
1. Is this position possible to arrive at (however unlikely) under the normal rules of chess?

[/ QUOTE ]
The chessbase link (http://www.chessbase.com/puzzle/games/puz7.htm) which you provided states clearly that the position is legal.


[ QUOTE ]
2.a. What Black's last move was?
b. Which of the light-squared White bishops is the promoted one?
c. If the pawn on b3 came from a2 or b2?


[/ QUOTE ]

I don't think that this problem can take total retro-analysis. Here's some sleuthing:

---> There are 5 White Pawns on the board, so at most 3 White promotions can have happened. One of them was of a Pawn promoting to Light-Squared White Bishop. (But we cannot define which square of the 8th rank was the square of that Pawn's promotion to LS White Bishop.) Respectively, there are 7 Black Pawns and 1 possible promotion by Black.

---> Both Kings are in legitimate positions.

---> We cannot define the last move by Black. It could have been even King from c6 to b7, for example (but not from b8 to b7, etc).

---> The LS White Bishop, at the start of the game, is on f1. Since both Panws at e2 and g2 are missing, that Bishop could have escaped legally. Bishop at h1 is in a perfectly achievable position through Bf1-g2-h1. Bishop at a2 can have gone there through a2, and a2 only, since the Pawn at c2 never moved. This means that the White Pawn at b3 was originally at b2 and simply stepped forward one square. Therefore, it is impossible to define which White Bishop is an original one and which was the result of a promotion.

---> The h5 Black Pawn was originally on g7. Therefore, the Black Pawn at f6 came from e7.







http://img.photobucket.com/albums/v720/DynastyPoker/puz7a.jpg

[beckham9]

starts out with b6 to d6, putting the horse in danger and forcing it to move, you can then move your bishop out from the back line, and can pressure black from there

[Chris_P]

[ QUOTE ]
starts out with b6 to d6, putting the horse in danger and forcing it to move, you can then move your bishop out from the back line, and can pressure black from there

[/ QUOTE ]

this makes no sense...

[Girchuck]

this is not checkers, friend.
d3-c2 is not mandatory, d3-d2 wins

[Girchuck]

This is not entirely true
Ka8 lets White to play b7, and the white king gets out

[Girchuck]

This is very inefficient, once white king gets to f2, it can take all the h pawns and probably the f6 pawn
To prevent white king from doing so, black must push the h pawn to h2 and another h pawn to h4

[MicroBob]

Haven't gone to the link to see the complete solution yet....just let me say that that really IS a pretty amazing solution. 271 freaking moves!!

Also...I am VERY happy that I didn't keep working on this and that I gave up after about 10-15 moves of pushing the king down to the a-rank and trying to swing it up somehow...blah blah blah.
I was 'initially' on the right track although the ideas of traingulation and forced-move (zugzwang??? it's been awhile for me) hadn't occured to me although looking back at this it probably should have.

I admittedly suck at chess-puzzles though.


This one really is pretty cool though the more I think about it.


On a not really related note: I believe I read that the longest possible chess-game without some draw being involved (by the 3-time position-repeition rule or 50-move no-capture and no-pawn move rule) is something like 5,428 moves.


This just reminded me of that little tid-bit since some people might guess that any problem with a 271 move solution would have a 3-time repetition or 50-move rule possibility SOMEWHERE in there to create a draw.