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# Solving the anti Cheating puzzle

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Here is the position. Here is the FEN 6k1/p1p4p/2p5/5PPP/p5p1/2p2pP1/P1P2P2/5KbN w - - 0 1

I will play white, my first move is 1.h6

Looks like a draw, can you show the winning line assuming black plays perfectly

the first thing to notice is that white's king and knight is going to be unable to support the advanced pawns. second thing to take note of is that white has to pt black into zugzwang in order to push the pawns, my initial thoughts is that we have to get a pawn on f6 and h6, with black having no pawn on h7, the king will also have to be on g8. thirdly this commonly know zugzwang position is not enough because the bishop needs to be captured somehow and because the king is the only piece that can move around freely we need to be on the correct tempo which black will be able to set by either playing 1 or 2 spaces on one of the pawn advance. with that in miond now i have to find a way to accomplish this in variations and either A) find the solution, B) note different possibilities.

great puzzle took me about 13-15 minutes to find the solution, and the rest of the time to explain my thoughts on it. It is a great puzzle. also i could not get the board to work so you guys wll just have to copy paste it in a pgn reader.
edit: the beginning move order is incorrect. 1.h6 Bh2 2.a3 Kf7 transposes and is  more accurate in sight of 1.a3 h6 stopping the pawn breakthrough.
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "6k1/p1p4p/2p5/5PPP/p5p1/2p2pP1/P1P2P2/5KbN w - - 0 1"]

1. a3 {i did consider this move because it gives white king space to lose a
tempo. I did not calculate it first because i thought it was critical to deal
with the kingside pawns first, which i realized is not the case.} (1. h6 {this
was the first move i considered} 1... a3 \$1 {the point is to take away the square
that allows white to lose a tempo this realization led me to find the solution}
2. Kxg1 (2. g6 hxg6 3. f6 {this idea no doesnt work because black can move
bishop back and forth} 3... Bh2 4. Ke1 Bg1 5. Kf1 Bh2 6. Ke1 Bg1 7. Kf1) 2...
Kf7 3. g6+ (3. f6 Kg6 {black repeats on g6, f7}) 3... hxg6 4. h7 Kg7 5. fxg6
{black can repeat with Kh8 Kg7 and white has no break through.}) (1. g6 {i
breifly looked at this but it is easy to evaluate because 2 connected pawns
can't break through.} 1... hxg6 2. hxg6 (2. h6 {i wanted to play this and have
f6 too but sadly thats not how the game works.}) 2... Kg7 {repetition with Kg7
and Kf6}) 1... Kf7 2. h6 \$1 {this now pts black's king in zugzwang, i will explain
the variations later.} 2... Bh2 3. Ke1 Bg1 4. Kd1 Bh2 5. Kc1 Bg1 6. Kb1 Bh2 7.
Ka2 Bg1 8. Ka1 Bh2 9. Kb1 Bg1 10. Kc1 Bh2 11. Kd1 Bg1 12. Ke1 Bh2 13. Kf1 a6
{now i have the sad job to keep going through this and play the long solution.}
14. Ke1 Bg1 15. Kd1 Bh2 16. Kc1 Bg1 17. Kb1 Bh2 18. Ka2 Bg1 19. Ka1 Bh2 20. Kb1
Bg1 21. Kc1 Bh2 22. Kd1 Bg1 23. Ke1 Bh2 24. Kf1 a5 25. Ke1 Bg1 26. Kd1 Bh2 27.
Kc1 Bg1 28. Kb1 Bh2 29. Ka2 Bg1 30. Ka1 Bh2 31. Kb1 Bg1 32. Kc1 Bh2 33. Kd1 Bg1
34. Ke1 Bh2 35. Kf1 c5 36. Ke1 Bg1 37. Kd1 Bh2 38. Kc1 Bg1 39. Kb1 Bh2 40. Ka2
Bg1 41. Ka1 Bh2 42. Kb1 Bg1 43. Kc1 Bh2 44. Kd1 Bg1 45. Ke1 Bh2 46. Kf1 c6 47.
Ke1 Bg1 48. Kd1 Bh2 49. Kc1 Bg1 50. Kb1 Bh2 51. Ka2 Bg1 52. Ka1 Bh2 53. Kb1 Bg1
54. Kc1 Bh2 55. Kd1 Bg1 56. Ke1 Bh2 57. Kf1 c4 58. Ke1 Bg1 59. Kd1 Bh2 60. Kc1
Bg1 61. Kb1 Bh2 62. Ka2 Bg1 63. Ka1 Bh2 64. Kb1 Bg1 65. Kc1 Bh2 66. Kd1 Bg1 67.
Ke1 Bh2 68. Kf1 c5 69. Ke1 Bg1 70. Kd1 Bh2 71. Kc1 Bg1 72. Kb1 Bh2 73. Ka2 Bg1
74. Ka1 Bh2 75. Kb1 Bg1 76. Kc1 Bh2 77. Kd1 Bg1 78. Ke1 Bh2 79. Kf1 {black is
finally in zuqzwang and now gives up the bishop} 79... Bg1 80. Kxg1 {sadly it
doesnt fix thier problem.} 80... Kg8 {at first glance this seems drawn, but
throse who know their pawn endgames will realize this pawn structre is winning.}
(80... Ke7 81. g6 Kf8 (81... hxg6 82. h7) 82. gxh7) (80... Kf8 81. g6 hxg6 82.
f6 Kg8 {same position as mainline}) (80... Ke8 81. g6 Kf8 (81... hxg6 82. h7)
82. gxh7) 81. g6 hxg6 82. f6 \$3 {black can not move his king because on of the
pawns i will promote.} 82... Kf7 (82... Kh7 83. f7) (82... g5 83. Kf1 Kf7 84.
h7) 83. h7 *

1.h6 Bh2 2.a3 Kf7 and now you go to the bottom left corner with your king to continually lose a move until your opponent runs out of moves because they're in zugzwang.

Chess_Player_lol wrote:
great puzzle took me about 13-15 minutes to find the solution, and the rest of the time to explain my thoughts on it. It is a great puzzle. also i could not get the board to work so you guys wll just have to copy paste it in a pgn reader.

[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "6k1/p1p4p/2p5/5PPP/p5p1/2p2pP1/P1P2P2/5KbN w - - 0 1"]

1. a3 {i did consider this move because it gives white king space to lose a
tempo. I did not calculate it first because i thought it was critical to deal
with the kingside pawns first, which i realized is not the case.} (1. h6 {this
was the first move i considered} 1... a3 \$1 {the point is to take away the square
that allows white to lose a tempo this realization led me to find the solution}
2. Kxg1 (2. g6 hxg6 3. f6 {this idea no doesnt work because black can move
bishop back and forth} 3... Bh2 4. Ke1 Bg1 5. Kf1 Bh2 6. Ke1 Bg1 7. Kf1) 2...
Kf7 3. g6+ (3. f6 Kg6 {black repeats on g6, f7}) 3... hxg6 4. h7 Kg7 5. fxg6
{black can repeat with Kh8 Kg7 and white has no break through.}) (1. g6 {i
breifly looked at this but it is easy to evaluate because 2 connected pawns
can't break through.} 1... hxg6 2. hxg6 (2. h6 {i wanted to play this and have
f6 too but sadly thats not how the game works.}) 2... Kg7 {repetition with Kg7
and Kf6}) 1... Kf7 2. h6 \$1 {this now pts black's king in zugzwang, i will explain
the variations later.} 2... Bh2 3. Ke1 Bg1 4. Kd1 Bh2 5. Kc1 Bg1 6. Kb1 Bh2 7.
Ka2 Bg1 8. Ka1 Bh2 9. Kb1 Bg1 10. Kc1 Bh2 11. Kd1 Bg1 12. Ke1 Bh2 13. Kf1 a6
{now i have the sad job to keep going through this and play the long solution.}
14. Ke1 Bg1 15. Kd1 Bh2 16. Kc1 Bg1 17. Kb1 Bh2 18. Ka2 Bg1 19. Ka1 Bh2 20. Kb1
Bg1 21. Kc1 Bh2 22. Kd1 Bg1 23. Ke1 Bh2 24. Kf1 a5 25. Ke1 Bg1 26. Kd1 Bh2 27.
Kc1 Bg1 28. Kb1 Bh2 29. Ka2 Bg1 30. Ka1 Bh2 31. Kb1 Bg1 32. Kc1 Bh2 33. Kd1 Bg1
34. Ke1 Bh2 35. Kf1 c5 36. Ke1 Bg1 37. Kd1 Bh2 38. Kc1 Bg1 39. Kb1 Bh2 40. Ka2
Bg1 41. Ka1 Bh2 42. Kb1 Bg1 43. Kc1 Bh2 44. Kd1 Bg1 45. Ke1 Bh2 46. Kf1 c6 47.
Ke1 Bg1 48. Kd1 Bh2 49. Kc1 Bg1 50. Kb1 Bh2 51. Ka2 Bg1 52. Ka1 Bh2 53. Kb1 Bg1
54. Kc1 Bh2 55. Kd1 Bg1 56. Ke1 Bh2 57. Kf1 c4 58. Ke1 Bg1 59. Kd1 Bh2 60. Kc1
Bg1 61. Kb1 Bh2 62. Ka2 Bg1 63. Ka1 Bh2 64. Kb1 Bg1 65. Kc1 Bh2 66. Kd1 Bg1 67.
Ke1 Bh2 68. Kf1 c5 69. Ke1 Bg1 70. Kd1 Bh2 71. Kc1 Bg1 72. Kb1 Bh2 73. Ka2 Bg1
74. Ka1 Bh2 75. Kb1 Bg1 76. Kc1 Bh2 77. Kd1 Bg1 78. Ke1 Bh2 79. Kf1 {black is
finally in zuqzwang and now gives up the bishop} 79... Bg1 80. Kxg1 {sadly it
doesnt fix thier problem.} 80... Kg8 {at first glance this seems drawn, but
throse who know their pawn endgames will realize this pawn structre is winning.}
(80... Ke7 81. g6 Kf8 (81... hxg6 82. h7) 82. gxh7) (80... Kf8 81. g6 hxg6 82.
f6 Kg8 {same position as mainline}) (80... Ke8 81. g6 Kf8 (81... hxg6 82. h7)
82. gxh7) 81. g6 hxg6 82. f6 \$3 {black can not move his king because on of the
pawns i will promote.} 82... Kf7 (82... Kh7 83. f7) (82... g5 83. Kf1 Kf7 84.
h7) 83. h7 *

You have to play 1.h6 first or else black will play ...h6. after 1.h6 Bh2 is forced because if Kxg1 is allowed you no longer need the a2 square to triangulate as black is already in zugzwang and has no bishop to waste moves with.

PopcornSC wrote:
Chess_Player_lol wrote:
great puzzle took me about 13-15 minutes to find the solution, and the rest of the time to explain my thoughts on it. It is a great puzzle. also i could not get the board to work so you guys wll just have to copy paste it in a pgn reader.

[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "6k1/p1p4p/2p5/5PPP/p5p1/2p2pP1/P1P2P2/5KbN w - - 0 1"]

1. a3 {i did consider this move because it gives white king space to lose a
tempo. I did not calculate it first because i thought it was critical to deal
with the kingside pawns first, which i realized is not the case.} (1. h6 {this
was the first move i considered} 1... a3 \$1 {the point is to take away the square
that allows white to lose a tempo this realization led me to find the solution}
2. Kxg1 (2. g6 hxg6 3. f6 {this idea no doesnt work because black can move
bishop back and forth} 3... Bh2 4. Ke1 Bg1 5. Kf1 Bh2 6. Ke1 Bg1 7. Kf1) 2...
Kf7 3. g6+ (3. f6 Kg6 {black repeats on g6, f7}) 3... hxg6 4. h7 Kg7 5. fxg6
{black can repeat with Kh8 Kg7 and white has no break through.}) (1. g6 {i
breifly looked at this but it is easy to evaluate because 2 connected pawns
can't break through.} 1... hxg6 2. hxg6 (2. h6 {i wanted to play this and have
f6 too but sadly thats not how the game works.}) 2... Kg7 {repetition with Kg7
and Kf6}) 1... Kf7 2. h6 \$1 {this now pts black's king in zugzwang, i will explain
the variations later.} 2... Bh2 3. Ke1 Bg1 4. Kd1 Bh2 5. Kc1 Bg1 6. Kb1 Bh2 7.
Ka2 Bg1 8. Ka1 Bh2 9. Kb1 Bg1 10. Kc1 Bh2 11. Kd1 Bg1 12. Ke1 Bh2 13. Kf1 a6
{now i have the sad job to keep going through this and play the long solution.}
14. Ke1 Bg1 15. Kd1 Bh2 16. Kc1 Bg1 17. Kb1 Bh2 18. Ka2 Bg1 19. Ka1 Bh2 20. Kb1
Bg1 21. Kc1 Bh2 22. Kd1 Bg1 23. Ke1 Bh2 24. Kf1 a5 25. Ke1 Bg1 26. Kd1 Bh2 27.
Kc1 Bg1 28. Kb1 Bh2 29. Ka2 Bg1 30. Ka1 Bh2 31. Kb1 Bg1 32. Kc1 Bh2 33. Kd1 Bg1
34. Ke1 Bh2 35. Kf1 c5 36. Ke1 Bg1 37. Kd1 Bh2 38. Kc1 Bg1 39. Kb1 Bh2 40. Ka2
Bg1 41. Ka1 Bh2 42. Kb1 Bg1 43. Kc1 Bh2 44. Kd1 Bg1 45. Ke1 Bh2 46. Kf1 c6 47.
Ke1 Bg1 48. Kd1 Bh2 49. Kc1 Bg1 50. Kb1 Bh2 51. Ka2 Bg1 52. Ka1 Bh2 53. Kb1 Bg1
54. Kc1 Bh2 55. Kd1 Bg1 56. Ke1 Bh2 57. Kf1 c4 58. Ke1 Bg1 59. Kd1 Bh2 60. Kc1
Bg1 61. Kb1 Bh2 62. Ka2 Bg1 63. Ka1 Bh2 64. Kb1 Bg1 65. Kc1 Bh2 66. Kd1 Bg1 67.
Ke1 Bh2 68. Kf1 c5 69. Ke1 Bg1 70. Kd1 Bh2 71. Kc1 Bg1 72. Kb1 Bh2 73. Ka2 Bg1
74. Ka1 Bh2 75. Kb1 Bg1 76. Kc1 Bh2 77. Kd1 Bg1 78. Ke1 Bh2 79. Kf1 {black is
finally in zuqzwang and now gives up the bishop} 79... Bg1 80. Kxg1 {sadly it
doesnt fix thier problem.} 80... Kg8 {at first glance this seems drawn, but
throse who know their pawn endgames will realize this pawn structre is winning.}
(80... Ke7 81. g6 Kf8 (81... hxg6 82. h7) 82. gxh7) (80... Kf8 81. g6 hxg6 82.
f6 Kg8 {same position as mainline}) (80... Ke8 81. g6 Kf8 (81... hxg6 82. h7)
82. gxh7) 81. g6 hxg6 82. f6 \$3 {black can not move his king because on of the
pawns i will promote.} 82... Kf7 (82... Kh7 83. f7) (82... g5 83. Kf1 Kf7 84.
h7) 83. h7 *

You have to play 1.h6 first or else black will play ...h6. after 1.h6 Bh2 is forced because if Kxg1 is allowed you no longer need the a2 square to triangulate as black is already in zugzwang and has no bishop to waste moves with.

yes i think you are correct, 1. a3 i overlooked 1...h6 which stops my plans, and is why it is needed to play it on the first move. I made a mistake in thinking a3 had to be played first.

I cannot imagine that an engine wouldn't find the win instantly nowadays

meeresgrund wrote:

I cannot imagine that an engine wouldn't find the win instantly nowadays

Well they don't. They likely never will or at least not in our lifetime. The solution is so long that the engine will have too many branches before it realizes the winning idea. If you let it sit until it reaches the same ply as the longest winning line then it might spot it but since the engines use methods to truncate lines it might be completely blind to the solution.

meeresgrund wrote:

I cannot imagine that an engine wouldn't find the win instantly nowadays

These long zugzwang endgames take advantage of the horizon effect of the engine.  The engine finally sees the solution once you get to about move 30 of the solution (when it has about another 30-40 moves to checkmate, but it is obvious there will be a forced material gain for White).  Humans can see this quickly because it is obvious the bishop can never go anywhere, nor can the Black king, so all White has to do is find a way to waste a move when necessary.  1. h6 keeps the king in the corner, and 2. a3 gives the king the way to triangulate.