Grandmasters and Engines Couldn't Solve This Puzzle.

[Jouni]

Very easy for good solver like Crystal (NNs are not):

Analysis by Crystal 080420 64 BMI2 4 cores


1.d8Q Nf7+
-+ (-2.26 --) Depth: 23/46 00:00:11 43997kN, tb=211872
1.d8Q
-+ (-2.04 ++) Depth: 23/46 00:00:11 46722kN, tb=226110
1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 Ba5+ 4.Ke7 e2 5.Bxe2 Nb4 6.Ne3 Bc7 7.Kf6 Kh8 8.Bd1 Bxg3 9.Kg6 Bf4 10.Nc2 Bd2 11.Nxb4 cxb4 12.Bb3 Bg5 13.Bc2 Kg8 14.Kf5 Bd2 15.Ke4 h5 16.Kf3 Kf7 17.Kg2 Ke6 18.Bd1 Kd5 19.Kf2 h4
-+ (-2.23) Depth: 23/50 00:00:12 49895kN, tb=243187
1.Nf6+
-+ (-2.14 ++) Depth: 24/47 00:00:14 58095kN, tb=309564
1.Nf6+
-+ (-2.04 ++) Depth: 24/47 00:00:14 58218kN, tb=311310
1.Nf6+
-+ (-1.89 ++) Depth: 24/47 00:00:14 58351kN, tb=312228
1.Nf6+
-+ (-1.69 ++) Depth: 24/47 00:00:14 58522kN, tb=313348
1.Nf6+
-/+ (-1.42 ++) Depth: 24/47 00:00:14 58773kN, tb=315130
1.Nf6+
-/+ (-1.06 ++) Depth: 24/47 00:00:14 58966kN, tb=315828
1.Nf6+
=/+ (-0.58 ++) Depth: 24/47 00:00:14 59229kN, tb=317826
1.Nf6+
= (0.02 ++) Depth: 24/47 00:00:14 60353kN, tb=319291
1.Nf6+
+/- (0.81 ++) Depth: 24/47 00:00:15 61431kN, tb=321060
1.Nf6+
+- (1.82 ++) Depth: 24/47 00:00:15 62517kN, tb=323049
1.Nf6+
+- (3.10 ++) Depth: 24/47 00:00:15 64445kN, tb=330295
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qe8 c4+ 6.Kc6 Kf3 7.Bd1+ Kg2 8.Qxe3 Bc5 9.Qxc3 Bf2 10.Be2 Nc5 11.Bxc4 Nce6 12.Bd5+ Kh3 13.Qe5 Nd4+ 14.Kd7 Ndf3 15.Qd6 Bxg3 16.Qxh6+ Kg4 17.Qf8 Ne5+ 18.Kd6
+- (3.74) Depth: 24/47 00:00:16 68679kN, tb=353516
1.Nf6+
+- (3.84 ++) Depth: 25/44 00:00:18 77051kN, tb=410444
1.Nf6+
+- (3.93 ++) Depth: 25/44 00:00:18 78059kN, tb=414263
1.Nf6+
+- (4.08 ++) Depth: 25/44 00:00:18 78344kN, tb=415666
1.Nf6+
+- (4.28 ++) Depth: 25/47 00:00:19 79622kN, tb=425647
1.Nf6+
+- (4.55 ++) Depth: 25/49 00:00:19 82361kN, tb=442017
1.Nf6+
+- (4.92 ++) Depth: 25/49 00:00:19 84131kN, tb=448916
1.Nf6+
+- (5.39 ++) Depth: 25/49 00:00:20 86013kN, tb=453682
1.Nf6+
+- (6.00 ++) Depth: 25/49 00:00:20 88433kN, tb=464891
1.Nf6+
+- (6.79 ++) Depth: 25/70 00:00:21 92624kN, tb=507947
1.Nf6+ Kg7
+- (3.64 --) Depth: 25/80 00:00:26 119mN, tb=821296
1.Nf6+
+- (5.72 ++) Depth: 25/80 00:00:26 120mN, tb=826861
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Kc6 Ba3 6.Qd1+ Kh3 7.Qf1+ Kxg3 8.Qg1+ Kf3 9.Bd1+ Ke4 10.Qg2+ Ke5 11.Qg3+ Kf6 12.Qf4+ Kg7 13.Qe5+ Kg6 14.Bc2+ Kh5 15.Qh2+ Kg4 16.Qe2+ Kf4 17.Qxa6 Nf3 18.Kd5 Nd4 19.Qxa3 Nxc2 20.Qxc5 Ne1 21.Qxc3 Ng2 22.Qf6+ Kg3
+- (7.21) Depth: 25/80 00:00:27 124mN, tb=859679
1.Nf6+
+- (7.31 ++) Depth: 26/50 00:00:28 132mN, tb=921733
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Kc6 Nf3 6.Qg8+ Kh3 7.Qe6+ Kg2 8.Qxe3 Nd4+ 9.Kb7 Nxc2 10.Qe4+ Kxg3 11.Qxc2 Nb8 12.Kxb8 h5 13.Qd3+ Kf4 14.Kb7 h4 15.Kc6 Kg4 16.Kb5 h3 17.Qd1+ Kh4 18.Qe1+ Kg4 19.Qf2 Ba3 20.Qe2+ Kg5 21.Qe5+ Kg4 22.Qe6+ Kg3 23.Qg6+ Kf4 24.Qf6+ Kg4 25.Qxc3 h2 26.Qe1 Bb4 27.Qe2+ Kg3
+- (7.35) Depth: 26/52 00:00:28 134mN, tb=929478
1.Nf6+
+- (7.45 ++) Depth: 27/57 00:00:30 144mN, tb=1058139
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Kc6 Nf3 6.Qg8+ Kh3 7.Qe6+ Kg2 8.Qxe3 Nd4+ 9.Kb7 Nxc2 10.Qe2+ Kxg3 11.Qxc2 Nb8 12.Kxb8 h5 13.Qd3+ Kf4 14.Kb7 h4 15.Kc6 Kg4 16.Kb5 h3 17.Qd1+ Kh4 18.Qe1+ Kg4 19.Qf2 h2 20.Qxh2 Kf5 21.Qd6 Ke4 22.Qd1 Ke5 23.Qd3 Kf6 24.Qe4 Kg5 25.Qf3 Kg6
+- (7.45) Depth: 27/57 00:00:30 144mN, tb=1059092

[peter]

Very easy for good solver like Crystal (NNs are not):

High time for Crystal NNUE

[MikeB]

This topic was already discussed a month ago.
Here:
http://talkchess.com/forum3/viewtopic.php?f=2&t=74317

Yes, as Peter pointed out above.

In the next release of Honey engines, I have incorporated GM Alexander Shashin's method for discovering best move, as coded by Andrea Manzo ( I believe he is the author ShashChess.)

A 5 second search on my machine, your mileage may vary:
[d]8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

Code: Select all

# Bla*D.exe



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  ######  #      #    # #      ####   #######  #     # # #    # # ## # #    # # #  # #    #    #     #
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  ######  ###### #    #  ####  #    #    #     ######  # #    # #    #  ####  #    # #####   ##### #####


    Black Diamond 091120  by Stockfish Developers as noted in the AUTHORS file
info string Found 55 tablebases

p f 8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1
s t 60
info string Hash Table: Windows Large Pages, 256 Mb
Confirmation: Threads set to 60
s h 4096
info string Hash Table: Windows Large Pages, 4096 Mb
Confirmation: Hash set to 4096 Mb
g mt 5
info string NNUE evaluation using eval.bin enabled
info depth 1 seldepth 2 multipv 1 score cp 394 nodes 3743 nps 1871500 tbhits 0 time 2 pv g4f6 h7g6
info depth 2 seldepth 4 multipv 1 score cp 191 nodes 32405 nps 10801666 tbhits 0 time 3 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6g7
info depth 3 seldepth 6 multipv 1 score cp 374 nodes 88262 nps 22065500 tbhits 0 time 4 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6g7 d8e7 g7g8 e7e8 g8g7 e8g6 g7h8
info depth 4 seldepth 8 multipv 1 score cp 345 nodes 137034 nps 34258500 tbhits 0 time 4 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6g7 d8e7 g7g8 e7e8 g8g7
info depth 5 seldepth 10 multipv 1 score cp 315 nodes 157814 nps 39453500 tbhits 0 time 4 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6f7 d8d7 f7f8 d7e7 f8g8 e7e8 g8g7 e8g6 g7f8
info depth 6 seldepth 12 multipv 1 score cp 314 nodes 175952 nps 43988000 tbhits 0 time 4 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6g7 d8e7 g7g8 e7e8 g8g7 e8g6 g7f8
info depth 7 seldepth 20 multipv 1 score cp 315 nodes 224057 nps 44811400 tbhits 0 time 5 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6f7 d8d7 f7f8 d7e7 f8g8 e7e8 g8g7 e8g6 g7f8 g6h6 f8e8 c2a4 e8f7
info depth 8 seldepth 16 multipv 1 score cp 320 nodes 261231 nps 52246200 tbhits 1 time 5 pv g4f6 h7g6 d1c2 g6f6 d7d8q f6g7 d8e7 g7g8 e7e8 g8g7 e8g6 g7f8 g6h6 f8f7 h6g5 c5c4 d6c6
info depth 9 seldepth 29 multipv 1 score cp -250 nodes 2521510 nps 84050333 tbhits 44 time 30 pv g4e3 b4a5 d1a4 g5e4 d6d5 e4f6 d5e6 h7g6 a4c2 g6g5 c2f5 a5d8 e6f7 f6d7 f5d7
info depth 10 seldepth 17 multipv 1 score cp -159 nodes 2908009 nps 85529676 tbhits 52 time 34 pv g4e3 b4a5 d6d5 h7h8 d1b3 h8g7 b3a4 g7f7 d5c4 a6b8 c4b5 b8d7 b5a5 d7e5
info depth 11 seldepth 20 multipv 1 score cp -171 nodes 3206924 nps 84392736 tbhits 57 time 38 pv g4e3 b4a5 d6c6 a6b8 c6d6 h7g7 d1a4 g5e4 d6d5 e4g3 d5c5 g3e4 c5b5 a5d8 b5b4 d8g5 e3c2 b8a6 b4c4 a6c5
info depth 12 seldepth 21 multipv 1 score cp -162 nodes 5471064 nps 84170215 tbhits 95 time 65 pv d6c6 g5f7 g4e3 b4a3 c6b6 a6b4 b6b5 h7g7 d1b3 f7d8 g3g4 g7f6 b5c4 h6h5
info depth 13 seldepth 29 multipv 1 score cp -170 nodes 7605164 nps 84501822 tbhits 463 time 90 pv d6c6 g5f7 g4e3 b4a3 d1b3 c5c4 b3a4 h7g7 c6b5 a6c5 e3c4 c5a4 c4a3 a4b2 b5b4 b2d3 b4c3
info depth 14 seldepth 31 multipv 1 score cp -171 nodes 9600446 nps 84214438 tbhits 872 time 114 pv d6c6 g5f7 g4e3 b4a3 e3c2 a6b4 c2b4 a3b4 d1b3 f7d8 c6c7 b4a5 c7d6 a5b6 d6d5 h7g7 d5c4 d8f7 c4c3 f7e5 b3a4
info depth 15 seldepth 29 multipv 1 score cp -171 nodes 10666160 nps 83985511 tbhits 1059 time 127 pv d6c6 g5f7 g4e3 b4a3 e3c2 a6b4 c2b4 a3b4 d1b3 f7d8 c6c7 b4a5 c7d6 h7g7 d6c5 d8e6 c5b5 a5c7 b5b4 e6f8 b4c3 f8d7 b3e6 d7c5 e6h3 c7g3 c3c4 c5e4 c4d4
info depth 16 seldepth 35 multipv 1 score cp -104 nodes 18771104 nps 82329403 tbhits 3532 time 228 pv d7d8q g5f7 d6d7 f7d8 d7d8 b4a5 d8d7 e3e2 d1e2 a6b4 g4e3 a5b6 e2d1 c5c4 e3c2 b4d3 d7c6 b6f2 c6d5 d3b2 d1f3 h7g6 f3e4 g6g5 c2a3 f2g3 a3c4
info depth 17 seldepth 37 multipv 1 score cp -117 nodes 22589832 nps 81847217 tbhits 9183 time 276 pv d7d8q g5f7 d6d7 f7d8 d7d8 b4a5 d8d7 a5c7 g4e3 c7g3 e3d5 g3e1 d1c2 h7g7 d7c6 h6h5 c6b5 a6b4 d5b4 c5b4 b5b4 g7f6 b4c4 h5h4 c4d3 h4h3 c2a4 f6e5 a4c6
info depth 18 seldepth 39 multipv 1 score cp -135 nodes 25793791 nps 81625920 tbhits 11497 time 316 pv d7d8q g5f7 d6d7 f7d8 d7d8 b4a5 d8d7 a5c7 g4e3 c7g3 e3d5 g3e1 d7c6 h6h5 d5c3 e1c3 d1h5 c3d4 h5e2 a6b4 c6d6 h7g6 e2c4 g6g5 c4f7 b4d3 f7c4 d3e5
info depth 19 seldepth 39 multipv 1 score cp -150 nodes 32217276 nps 80745052 tbhits 15944 time 399 pv d7d8q g5f7 d6d7 f7d8 d7d8 b4a5 d8d7 a5c7 g4e3 c7g3 d7c6 h7g6 c6b5 a6c7 b5c4 g3f2 e3f1 f2d4 f1g3 c7e6 d1c2 g6g5 c2d1 h6h5 g3h5 c3c2 d1c2
info depth 20 seldepth 43 multipv 1 score cp -157 nodes 36541627 nps 80311268 tbhits 29656 time 455 pv d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 g4e3 c7g3 d7c6 h7g6 c6b6 a6c7 d1c2 g6g5 e3d1 c7e6 d1c3 g3c7 b6c6 e6d4 c6c7 d4c2 c7d6 h6h5 d6c5 h5h4 c3e4 g5f4 e4f2 f4f3
info depth 21 seldepth 50 multipv 1 score cp -154 nodes 53127656 nps 79771255 tbhits 65570 time 666 pv d7d8q g5f7 d6d7 f7d8 d7d8 b4a5 d8d7 a5c7 g4e3 c7g3 d7c6 h7g6 c6b6 a6c7 d1c2 g6g5 e3d1 g3e5 d1c3 c5c4 c3e4 g5f4 b6c5 c4c3 c5c4 h6h5 e4c3 e5c3 c4c3 h5h4 c2d3 h4h3 d3f1 h3h2 f1g2 f4e3 g2h1
info depth 22 seldepth 60 multipv 1 score cp 261 nodes 182536099 nps 84979561 hashfull 392 tbhits 437275 time 2148 pv g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8f6 g4g3 f6e5 g3f2 e5h2 f2e1 h2h1 e1e2 d6e5 c5c4 e5d5 g5h3 h1h3 e2d2 h3g2 e3e2 d5c4 d2c2 g2e2 c2b1 e2d1 b1b2 d1b3 b2c1 b3a2 c3c2 c4b3 a6c5 b3b4 c5e4[
info depth 23 seldepth 48 multipv 1 score cp 280 nodes 222301714 nps 86566088 hashfull 459 tbhits 610831 time 2568 pv g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8f6 g4g3 f6e5 g3g2 e5e3 c5c4 d6d5 b4c5 e3c3 c5f2 d5c4 a6c5 c3f6 f2e3 f6h6 c5d7 h6g7 d7b6 c4d3 e3f4 g7d4 g5h3 d4b6 g2g3 c2d1 f4c1 d3c4 c1g5
info depth 24 seldepth 52 multipv 1 score cp 300 lowerbound nodes 264607104 nps 87821806 hashfull 527 tbhits 785184 time 3013 pv g4f6
info depth 24 seldepth 52 multipv 1 score cp 306 lowerbound nodes 274399188 nps 88061356 hashfull 543 tbhits 821004 time 3116 pv g4f6
info depth 24 seldepth 52 multipv 1 score cp 312 nodes 302758547 nps 88655504 hashfull 577 tbhits 905965 time 3415 pv g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8f6 g4g3 f6e5 g3f2 e5h2 f2e1 h2h1 e1e2 d6e5 c5c4 e5d5 g5h3 h1h3 e2d2 h3g2 e3e2 d5c4 d2c2 g2e2 c2b1 e2d1 b1b2 d1b3 b2c1 b3a2 b4e7 c4c3 e7f6 c3c4 a6c5 c4c5 f6e7 c5c4 h6h5 a2e2
info depth 25 seldepth 50 multipv 1 score cp 329 lowerbound nodes 331603344 nps 89260657 hashfull 607 tbhits 1016264 time 3715 pv g4f6
info depth 25 seldepth 50 multipv 1 score cp 332 lowerbound nodes 344620458 nps 89511807 hashfull 623 tbhits 1069663 time 3850 pv g4f6
info depth 25 seldepth 54 multipv 1 score cp 336 lowerbound nodes 376159427 nps 90076491 hashfull 652 tbhits 1176932 time 4176 pv g4f6
info depth 25 seldepth 54 multipv 1 score cp 342 lowerbound nodes 394772205 nps 90378252 hashfull 668 tbhits 1233482 time 4368 pv g4f6
info depth 25 seldepth 54 multipv 1 score cp 342 nodes 456838707 nps 91331208 hashfull 710 tbhits 1431967 time 5002 pv g4f6
bestmove g4f6 ponder h7g7

In addition, this version will have embedded 55 syzygy tablebases (WDL Only) - and will weigh in at a bloated 70 MB or so. Clearly not for everyone.

In single thread mode with 4096 hash, it will lock on to Nf6 in about 30 seconds on my machine, ymmv.

Code: Select all

info 30 seconds
info depth 27 seldepth 58 multipv 1 score cp -224 nodes 54211692 nps 1806996 hashfull 266 tbhits 58495 time 30001 pv d7d8q g5f7
info depth 28 seldepth 58 multipv 1 score cp -133 lowerbound nodes 54626376 nps 1806846 hashfull 268 tbhits 58766 time 30233 pv g4f6
info depth 28 seldepth 58 multipv 1 score cp -72 lowerbound nodes 58101561 nps 1806191 hashfull 283 tbhits 66326 time 32168 pv g4f6

info 40 seconds
info depth 27 seldepth 58 multipv 1 score cp -72 nodes 72045885 nps 1801102 hashfull 351 tbhits 89323 time 40001 pv g4f6
info depth 28 seldepth 58 multipv 1 score cp 5 lowerbound nodes 72184649 nps 1800564 hashfull 351 tbhits 90463 time 40090 pv g4f6
info depth 28 seldepth 58 multipv 1 score cp 103 lowerbound nodes 81782348 nps 1800936 hashfull 390 tbhits 96790 time 45411 pv g4f6

info 50 seconds
info depth 27 seldepth 58 multipv 1 score cp 103 nodes 90696891 nps 1813901 hashfull 416 tbhits 143865 time 50001 pv g4f6
info depth 28 seldepth 70 multipv 1 score cp 228 lowerbound nodes 99125671 nps 1820055 hashfull 441 tbhits 154069 time 54463 pv g4f6

info 60 seconds
info depth 27 seldepth 70 multipv 1 score cp 228 nodes 110823973 nps 1847035 hashfull 487 tbhits 228289 time 60001 pv g4f6

info 70 seconds
info depth 27 seldepth 70 multipv 1 score cp 228 nodes 132343467 nps 1890593 hashfull 546 tbhits 372410 time 70001 pv g4f6

info 80 seconds
info depth 27 seldepth 70 multipv 1 score cp 228 nodes 152686838 nps 1908561 hashfull 606 tbhits 497980 time 80001 pv g4f6

info 90 seconds
info depth 27 seldepth 70 multipv 1 score cp 228 nodes 174120843 nps 1934654 hashfull 653 tbhits 635929 time 90001 pv g4f6

info 100 seconds
info depth 27 seldepth 70 multipv 1 score cp 228 nodes 195406675 nps 1954047 hashfull 701 tbhits 777015 time 100001 pv g4f6
info depth 28 seldepth 72 multipv 1 score cp 231 nodes 207774756 nps 1962805 hashfull 724 tbhits 824184 time 105856 pv g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d6c6 b4a3 d8d1 g4g3 d1e1 g3f4 e1f1 f4g3 f1a6 g5e6 c2d1 e6d4 c6d5 c3c2 d1c2 g3f2 a6f6 f2e1 c2a4 e3e2 f6f4 a3b4 d5e4 b4d2 f4f8 d2b4 f8f6 b4c3 e4d3 c3d2 a4d7 d4b3 f6e5 c5c4 d3c4

info 110 seconds
info depth 28 seldepth 72 multipv 1 score cp 231 nodes 215780644 nps 1961624 hashfull 734 tbhits 840802 time 110001 pv g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d6c6 b4a3 d8d1 g4g3 d1e1 g3f4 e1f1 f4g3 f1a6 g5e6 c2d1 e6d4 c6d5 c3c2 d1c2 g3f2 a6f6 f2e1 c2a4 e3e2 f6f4 a3b4 d5e4 b4d2 f4f8 d2b4 f8f6 b4c3 e4d3 c3d2 a4d7 d4b3 f6e5 c5c4 d3c4
info depth 29 seldepth 58 multipv 1 score cp 234 lowerbound nodes 215851703 nps 1961592 hashfull 734 tbhits 840956 time 110039 pv g4f6
info depth 29 seldepth 58 multipv 1 score cp 237 lowerbound nodes 218917875 nps 1960874 hashfull 737 tbhits 845194 time 111643 pv g4f6
info depth 29 seldepth 58 multipv 1 score cp 241 lowerbound nodes 221446867 nps 1960643 hashfull 741 tbhits 849133 time 112946 pv g4f6
info depth 29 seldepth 58 multipv 1 score cp 247 lowerbound nodes 224269020 nps 1960804 hashfull 747 tbhits 853189 time 114376 pv g4f6

[yurikvelo]

But Stockfish NNUE can solve this puzzle in under 7 minutes on this system.

I went through engine mistakes to see where and why they stuck.

I've reach this position (+24 plies from root)
[pgn]
[SetUp "1"]
[FEN "8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1"]

[PlyCount "24"]

1. Nf6+ Kg7 2. Nh5+ Kg6 3. Bc2+ Kxh5 4. d8=Q Nf7+ 5. Ke6 Nxd8+ 6. Kf5 e2 7.
Be4 e1=N 8. Bd5 c2 9. Bc4 c1=N 10. Bb5 Nc7 11. Ba4 Nb3 12. Bxb3 Nf3 *
[/pgn]

this position is mate in 3 plies (+M2)
but even at D=3 (which is effectively D=27 from root) it receive -7.90 by latest SF-Dev (NNUE = On)

due to heavily negative score, this kind of positions in tree are early pruned

Going from -7.90 to +M2 just in D=D+1 ply is very weird and rare

Code: Select all

 1	66	-8,16	13.g4+ Kh4
 2	263	-8,34	13.g4+ Kh4 14.Kg6
 3	399	-7,90	13.g4+ Kh4 14.Kg6 Kxg4
 4	1k	+M2	13.Bd1 Nc6 14.Bxf3+

I've checked with Komodo 14, it gives +M2 @ D=1

[MMarco]

With a single thread on my three years old phone, Crystal 3.0 needs only a few seconds to play Nf6+:

Code: Select all

[18] >=1.78 Nf6+
d:18/36 1:Nf6+ t:15.21 n:3543k nps:232k tb:662 h:3

After 2 min:

Code: Select all

[24] 5.74 Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8Q Kg4 Qf6 Kxg3 Qe5+ Kg2 Qxe3 c4+ Kd5 Bc5 Qxc3 Bf2 Qxc4 Nc5 Bf5 Kg1 Qg4+ Kf1 Kc4 Bg1 Qh5 Kg2 Qe2+ Kg3 Qg4+ Kh2 Qd1 Kg2 Qd5+ Kh2 Qd6+ Kg2 Qf4 Bf2 Bc2 Nce6 Be4+ Kf1 Qc1+ Ke2 Qc2+ Ke3 Ba8 h5 Qc1+ Ke2
d:25/52 1:Nf6+ t:127.6 n:30447k nps:238k tb:74246 h:28

[h1a8]

With a single thread on my three years old phone, Crystal 3.0 needs only a few seconds to play Nf6+:

Code: Select all

[18] >=1.78 Nf6+
d:18/36 1:Nf6+ t:15.21 n:3543k nps:232k tb:662 h:3

After 2 min:

Code: Select all

[24] 5.74 Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8Q Kg4 Qf6 Kxg3 Qe5+ Kg2 Qxe3 c4+ Kd5 Bc5 Qxc3 Bf2 Qxc4 Nc5 Bf5 Kg1 Qg4+ Kf1 Kc4 Bg1 Qh5 Kg2 Qe2+ Kg3 Qg4+ Kh2 Qd1 Kg2 Qd5+ Kh2 Qd6+ Kg2 Qf4 Bf2 Bc2 Nce6 Be4+ Kf1 Qc1+ Ke2 Qc2+ Ke3 Ba8 h5 Qc1+ Ke2
d:25/52 1:Nf6+ t:127.6 n:30447k nps:238k tb:74246 h:28

What's the rating for Crystal? And what app for android has crystal 3.0?

[MMarco]

I have not seen a rating list with Crystal 3.0 on it yet. A quick test of mine shows -120 elo to CFish 050920: http://talkchess.com/forum3/viewtopic.p ... 10#p860553

I used Droidfish. Just put the engine in Droidfish uci folder and select the engine in the GUI: https://www.mirrored.to/files/H0F7ERYR/ ... o.7z_links

The engine do sometime crash though, especially on more than 1 thread. It was compiled by "Skynet" and posted on the Outskirts chess forum