The chess position with the most possible legal moves?

[RJN]

I was curious what are some known positions with a large number of possible legal moves. I have done some googling, and was wondering if anyone else has any examples. My searching seems to show it's difficult to get above 100 or so moves for a legal position.

I would assume positions with many Queens have the most possible moves, vs positions with no promotions yet. So, with that assumption, I feel this should be broken into several categories:

1) Positions where no promotions have taken place yet (but one is possible on the move, with underpromotions being different moves).

2) Positions that have promoted pieces, with crazy things like 9 Queens.

3) I would also be curious to see what positions in real recorded games had many possible moves.

[Brunetti]

1) Positions where no promotions have taken place yet (but one is possible on the move, with underpromotions being different moves).

144 moves, Dr. Jeno Ban, 1960
[d]n1r1r1b1/1P1P1P1P/1Q6/3NBNK1/R7/4p1p1/3PBPkP/2R5 b - - 0 1

2) Positions that have promoted pieces, with crazy things like 9 Queens.

218 moves, A. S. M. Dickins, 1968
[d]3Q4/1Q4Q1/4Q3/2Q4R/Q4Q2/3Q4/1Q4Rp/1K1BBNNk w - -

3) I would also be curious to see what positions in real recorded games had many possible moves.

75 (White's 25th) in Podhorzer - Palda, XVI Trebitsch-Turnier, Vienna 1933
[pgn]1.d4 d5 2.Nf3 Nf6 3.c4 e6 4.Nc3 c6 5.e3 Be7 6.Bd3 Nbd7 7.O-O O-O 8.Qe2 Qc7 9.e4 dxe4 10.Nxe4 Nxe4 11.Bxe4 Bf6 12.Re1 Re8 13.Ne5 g6 14.Bf4 Qb6 15.Rad1 Qa5 16.Nxc6 Qxa2 17.Ra1 Qb3 18.Ra3 Qb6 19.c5 Nxc5 20.dxc5 Qxc5 21.Rc1 Qb6 22.Ne5 Qd6 23.Qb5 Qf8 24.Ng4 Bg7 25.Bd6 Re7 26.Qc5 1-0[/pgn]
Alex

[Volker Annuss]

3) I would also be curious to see what positions in real recorded games had many possible moves.

I found this one in Walter Eingenmann's Comp2007_ECO_A.pgn with 119 legal moves at move 91.

[pgn]
[Event "Lyapko_AthlonXP1700_30Min"]
[Site "?"]
[Date "2004.??.??"]
[Round "11"]
[White "Skaki 1.19"]
[Black "Damas 6.0"]
[Result "0-1"]
[ECO "A06"]
[PlyCount "182"]
[EventDate "2004.??.??"]
[Source "W.Eigenmann"]
[SourceDate "2002.01.01"]

1. Nf3 d5 2. e3 Bg4 3. c4 Bxf3 4. gxf3 e6 5. cxd5 exd5 6. Qb3 b6 7. Qa4+ c6 8.
Qd1 Nd7 9. Bg2 Bd6 10. Nc3 Qc8 11. f4 Ne7 12. Bf1 O-O 13. Be2 d4 14. exd4 Bxf4
15. Bg4 f5 16. Be2 Re8 17. Bc4+ Kh8 18. Ne2 Bd6 19. d3 a5 20. O-O Qb8 21. f4
Nf6 22. Bf7 Rf8 23. Bb3 Ned5 24. a4 Bb4 25. Bxd5 Nxd5 26. Rf3 Re8 27. Kf2 Ra7
28. Ra2 Rae7 29. b3 Nc3 30. Nxc3 Bxc3 31. Bd2 Bxd4+ 32. Kf1 Qc8 33. Rc2 c5 34.
Rc4 Kg8 35. Rg3 Bb2 36. b4 axb4 37. Qb3 Qe6 38. Qxb2 Qe2+ 39. Kg1 Qd1+ 40. Kg2
Re2+ 41. Kh3 Qf1+ 42. Kh4 Rxh2+ 43. Kg5 Rg2 44. Kxf5 Rxg3 45. Qe5 Qxd3+ 46. Re4
Rf8+ 47. Ke6 Rg6+ 48. Qf6 Qxe4+ 49. Kd6 Rgxf6+ 50. Kd7 Qe8+ 51. Kc7 Qxa4 52.
Kb7 Qd7+ 53. Ka6 Qxd2 54. f5 Qd8 55. Kb5 Rxf5 56. Kc4 Rf4+ 57. Kb5 b3 58. Ka6
b2 59. Kb5 b1=Q+ 60. Kc6 Qe4+ 61. Kb5 Qee8+ 62. Ka6 g5 63. Ka7 Qb8+ 64. Ka6
Qec8+ 65. Kb5 c4 66. Kb4 c3+ 67. Kb3 c2 68. Ka2 c1=Q 69. Kb3 h5 70. Ka2 Rf2+
71. Kb3 Q1c7 72. Ka4 b5+ 73. Ka3 Q7d8 74. Kb3 b4 75. Ka4 b3 76. Ka3 b2 77. Ka2
b1=Q+ 78. Ka3 Q1b7 79. Ka4 g4 80. Ka3 h4 81. Ka4 g3 82. Ka3 h3 83. Ka4 g2 84.
Ka3 g1=Q 85. Ka4 h2 86. Ka3 h1=Q 87. Ka4 Qgg7 88. Ka3 Qdf6 89. Ka4 Rd8 90. Ka5
Rd1 91. Ka4 Qbb2 0-1
[/pgn]

[Ajedrecista]

Hello Rob:

Please take a look at the following thread:

max amount of moves from a position?

You will see there a composed position with 218 legal moves.

The tool called Joined (by Andreas Stable) also finds the position with more legal moves if you feed it with a PGN. Image taken from Adam Hair's web (fourth line of text in the image):



You can run Joined with PGN files of CCRL, CEGT, etc. and find interesting results by yourself. Good luck!

------------

@Volker: this game was an abuse like yesterday game Brazil 1-7 Germany.

Regards from Spain.

Ajedrecista.

[cdani]

Mate in 4:
[d]qqqqqqqk/7q/8/8/8/8/Q7/KQQQQQQQ w - - 0 1

[RJN]

Thanks for the feedback, especially the great utility JOINED.

While not a record, when I ran JOINED on my database of 5M games, it found 115 possible moves for white on move #97 in the real game below. It was a bit disappointing though, as this is another semi-artificial position. White appears to just be punishing someone who refuses to resign. So maybe I needed another category, real games that are not absurdly lopsided. (although I guess it is possible that black thought white would lose on time trouble, or die of a sudden heart attack!)

PS: to Daniel Jose, your position is only 102 moves....I think. That's what Komodo TCEC reports.

115 moves possible:

[d]1Q3Q2/P3R3/7Q/5K2/2Q5/k7/8/6Q1 w - - 1 97

[pgn]
[Event "?"]
[Site "?"]
[Date "2003.??.??"]
[Round "?"]
[White "Dietrich, Martin"]
[Black "Schmucklermann, Alexandra"]
[Result "1-0"]
[ECO "A41"]
[Opening "Neo-Old Indian"]
[Variation "Modern, 3.Bf4 Bg7"]
[TimeControl "240+6"]
[Termination "normal"]
[PlyCount "193"]
[WhiteType "human"]
[BlackType "human"]

1. d4 g6 2. Nf3 Bg7 3. Bf4 d6 4. e3 e6 5. c4 Ne7 6. Nc3 O-O 7. Be2 Nd7 8.
O-O c5 9. Bxd6 b6 10. d5 Nf6 11. dxe6 Bxe6 12. Ng5 Bd7 13. Bf3 Rc8 14. Bb7
Re8 15. Qc2 Bf5 16. Bxe7 Rxe7 17. e4 Bd7 18. Bxc8 Qxc8 19. Rad1 Bc6 20. Nd5
Re8 21. Rfe1 h6 22. Nf3 Qd7 23. h3 Ba4 24. b3 Bc6 25. Qd3 Qe6 26. e5 Nd7
27. Nf6+ Nxf6 28. exf6 Qxf6 29. Rxe8+ Bxe8 30. Qd8 Qxd8 31. Rxd8 Kf8 32.
Ra8 a5 33. Ra6 Bc3 34. Rxb6 Bb4 35. Rb8 Ke7 36. Ne5 g5 37. Kf1 f6 38. Nd3
Bd7 39. Nxb4 cxb4 40. Rb7 Ke6 41. Ra7 Kd6 42. Rxa5 Be6 43. Ra6+ Kd7 44. Ke2
Ke7 45. Ke3 Bc8 46. Rb6 Kd7 47. Kd4 Kc7 48. Rxf6 Kb7 49. Kc5 Kc7 50. Rxh6
Bd7 51. Kxb4 Bc6 52. g3 Kb6 53. c5+ Ka6 54. Rxc6+ Kb7 55. Rg6 Kc7 56. Kc4
Kd7 57. Kd4 Kc7 58. Rd6 Kb7 59. Ke5 Kc7 60. Kf5 Kb7 61. Kxg5 Kc7 62. h4 Kb7
63. h5 Kc7 64. h6 Kb7 65. h7 Kc7 66. h8=Q Kb7 67. f4 Kc7 68. f5 Kb7 69. f6
Kc7 70. f7 Kb7 71. f8=Q Ka7 72. Rc6 Kb7 73. Qhh6 Ka7 74. Kf5 Kb7 75. g4 Ka7
76. g5 Kb7 77. g6 Ka7 78. g7 Kb7 79. g8=Q Ka7 80. Rc8 Kb7 81. Re8 Ka7 82.
c6 Kb6 83. a4 Kc7 84. Re7+ Kb6 85. c7+ Ka5 86. c8=Q Kb4 87. Qcc4+ Ka3 88.
Qg1 Kb2 89. a5 Ka3 90. a6 Ka2 91. a7 Kb2 92. b4 Ka3 93. b5 Kb2 94. b6 Ka3
95. b7 Kb2 96. b8=Q+ Ka3 97. a8=Q# 1-0[/pgn]

[Brunetti]

So maybe I needed another category, real games that are not absurdly lopsided.

See my answer above.

(although I guess it is possible that black thought white would lose on time trouble

White can't lose this game


Alex

[SMIRF]

Have a look of the bottom of following web-site:

http://www.10x8.net/chess/Zahlen.html

[bnst]

I am the author of the joined program. It is very old now, but if somebody need a 64-bit compile or other versions of the program I might be able to make it available.
Regards
Andreas

[RJN]

I am the author of the joined program. It is very old now, but if somebody need a 64-bit compile or other versions of the program I might be able to make it available.
Regards
Andreas

That would be great. It's still pretty fast as is, 5M games processed in about an hour.