interesting endgame in CCCC

[jdart]

This wound up in one of the interminable Queen endgames where there are a zillion checks.

I am not clear if White could have drawn or not. I put in a couple annotations where I think there might be better play.

But I only have 5-man TBs so am not sure.

--Jon

[pgn][Event "CCCC 1: Rapid Rumble (15|5) Stage 1"] [Site "Chess.com"] [Date "2018.09.06"] [Round "?"] [White "Fire 7.1"] [Black "Komodo 2118.00"] [Result "0-1"] [ECO "C08"] [WhiteElo "3326"] [BlackElo "3226"] [PlyCount "444"] [EventDate "2018.??.??"] [EventType "rapid"] [TimeControl "900+5"] 1. e4 e6 2. d4 d5 3. Nd2 c5 4. exd5 exd5 5. Ngf3 Nf6 6. Bb5+ Bd7 7. Bxd7+ Nbxd7 8. O-O Be7 9. dxc5 Nxc5 10. Nb3 Nce4 11. Nfd4 Nd6 12. c3 O-O 13. Qc2 Re8 14. Re1 Nc4 15. Bg5 Qb6 16. Nf5 Bf8 17. Ne3 Qa6 18. Nd4 h6 19. Bxf6 Nxe3 20. Rxe3 Rxe3 21. fxe3 Qxf6 22. Rf1 Qe7 23. Qd3 g6 24. Nc2 Rd8 25. Qd4 a5 26. Qb6 Ra8 27. Qb3 h5 28. Qxd5 Bh6 29. Qf3 Rd8 30. Qe2 Qe4 31. Rf3 Rd3 32. Kf2 a4 33. a3 Rd6 34. Kg1 f5 35. Nd4 Kg7 36. h3 Rd8 37. Kf2 Re8 38. Qd2 Bg5 39. Nc2 Kh6 40. Kg1 Qe6 41. Qc1 Qd6 42. Nd4 Qe5 43. Nc2 Qb5 44. Nd4 Qe5 45. Nc2 Qb5 46. Nd4 Qd3 47. Kf2 Kh7 48. Ne2 Qd6 49. Kg1 Qe5 50. Nf4 Qe4 51. Kh2 Be7 52. Ne2 Bg5 53. Nf4 Rd8 54. Kg1 Kh6 55. Qe1 Qe7 56. Qc1 Qd7 57. Qe1 Qe7 58. Qc1 Qd7 59. Qe1 h4 60. Qc1 Qc6 61. Rf2 Qb6 62. Rf3 Qd6 63. Qe1 Qe5 64. Qc1 Kh7 65. Ne2 Kg7 66. Nd4 Rd6 67. Kh1 Qe4 68. Kg1 Rd5 69. Kf2 Re5 70. Qd2 Re8 71. Nc2 Qc6 72. Nb4 Qe6 73. Nc2 Kh7 74. Kg1 Qe4 75. Kf2 Rd8 76. Qc1 Qc4 77. Kg1 Kh6 78. Rf2 Rd3 79. Rf3 Qe6 80. Kf2 Qb3 81. Ke2 Qc4 82. Kf2 Rd7 83. Kg1 Rd3 84. Nb4 Rd6 85. Nc2 Rd7 86. Kf2 Rd8 87. Kg1 Rd6 88. Kh2 Rd3 89. Kg1 Qe6 90. Qe1 Qe4 91. Qc1 Kg7 92. Qe1 Bh6 93. Kh2 Kh7 94. Kg1 Bg5 95. Qe2 Kh6 96. Qe1 Rd6 97. Nd4 Rd8 98. Qc1 Rd5 99. Qd2 b6 100. Qc1 Re5 101. Kf2 Re8 102. Ke2 Qd5 103. Qd1 Qa2 104. Qc2 Re5 105. Kf2 Kg7 106. Qd2 Qd5 107. Qc2 Kh7 108. Ke2 Qa2 109. Kf2 Kg7 110. Ke2 Qa1 111. Kf2 Re7 112. Ne2 Rd7 113. Nd4 Kh6 114. Ke2 Qg1 115. Kd3 Re7 116. Qf2 Qc1 117. Qd2 Qg1 118. Qf2 Qc1 119. Qe2 Re4 120. Qd2 Qg1 121. Qe2 Kg7 122. Kd2 b5 123. Nc2 b4 124. axb4 Qb1 125. Qa6 Qxb2 126. Qxa4 Re7 127. Qc6 Bf6 128. g4 hxg3 129. Rxg3 Ra7 130. Kd3 Qc1 131. Rg2 Re7 132. Qf3 Rc7 133. Rxg6+ Kxg6 134. Qg3+ Kh6 135. Qf4+ Bg5 136. Qd6+ Kh5 137. Qxc7 Qd1+ 138. Kc4 Qxc2 139. Qh7+ Bh6 140. Kb5 Qe4 141. c4 Kg5 142. h4+ Kh5 143. c5 Qd5 144. Kb6 Qd8+ 145. Kb5 Qd5 146. Kb6 Qd8+ 147. Kb5 Qb8+ 148. Ka4 Qe8+ 149. b5 Qe6 150. Ka5 Kg4 151. b6 Bxe3 152. Qg7+ Kxh4 153. b7 Bd2+ 154. Kb5 Qb3+ 155. Kc6 Qa4+ 156. Kc7 Bf4+ 157. Kb6 Qb3+ 158. Ka6 Qe6+ 159. Ka7 Be5 160. Qf8 Kg4 161. Qc8 Qa2+ 162. Kb6 Qb2+ 163. Ka6 Qa3+ 164. Kb6 Qb4+ 165. Ka6 Qc4+ 166. Kb6 Qf7 ({maybe better is} 166... Qb4+) 167. Ka6 Qd5 168. Kb6 (168. Ka7 $5) 168... Kg5 169. Qf8 Qb3+ 170. Kc6 Qe6+ 171. Kb5 f4 172. c6 Qb3+ 173. Ka6 Kg4 174. Qc8+ Kg3 175. Qd8 Qa4+ 176. Kb6 Qb4+ 177. Ka6 Qc5 178. Qg8+ Kf2 179. Qa2+ Kf3 180. Qb3+ Kg2 181. Qa2+ Kh3 182. Qb3+ Kh4 183. Qb5 Qc3 184. Ka7 Qa3+ 185. Kb6 Bb8 186. Qb1 Qe3+ 187. Ka6 Kg5 188. Qb2 Kf5 189. Qh8 Qe5 190. Qh7+ Ke6 191. Qd7+ Kf6 192. Qd8+ Kf5 193. Qd3+ Kg5 194. Qd8+ Kg4 195. Qg8+ Kf3 196. Qb3+ Ke4 197. Qc4+ Ke3 198. Qb4 f3 199. Qe1+ Kd4 200. Qa1+ Ke4 201. Qb1+ Kf4 202. Qc1+ Kf5 203. Qb1+ Kf6 204. Qb4 Qe2+ 205. Kb6 Qe3+ 206. Ka6 f2 207. Qf8+ Kg6 208. Qg8+ Kf5 209. Qf7+ Ke4 210. Qc4+ Qd4 211. Qe6+ Kd3 212. Qb3+ Kd2 213. Qa2+ Ke3 214. Qe6+ Qe4 215. Qh6+ Kd3 216. Qf6 Qf4 217. Qg6+ Kc3 218. Qg7+ Kb3 219. Qa1 f1=Q+ 220. Qxf1 Qxf1+ 221. Kb6 Kb4 222. c7 Qb5# { normal} 0-1 [/pgn]

[Spliffjiffer]

hi Jon,
after some back and forth SF-dev says 0.00 after 166.Kb6...seems like a draw eighter way !??...yes, SF says 168.Kb6?? is loosing and gives a draw-score after your suggested 168.Ka7!!(only move)...i have installed some 6-men-TB but not all...this is just a quick observation and not a deep analysis !

[Eelco de Groot]

hi Jon,
after some back and forth SF-dev says 0.00 after 166.Kb6...seems like a draw eighter way !??...yes, SF says 168.Kb6?? is loosing and gives a draw-score after your suggested 168.Ka7!!(only move)...i have installed some 6-men-TB but not all...this is just a quick observation and not a deep analysis !

Hi guys

I think the search or evaluation of Stockfish would have to be taken with a pinch of salt here. Maybe Komodo sees it much better. Even after seeing that White loses in the game, if you then go back:

[d]2Q5/1P6/K7/2P1bp2/6k1/8/1q6/8 b - -

Engine: Kaissa IV (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

52 21:16 -0.90 163...Qa3+ 164.Kb5 Qb2+ 165.Ka6 Qa2+
166.Kb6 Qf7 167.Ka6 Qc4+ 168.Kb6 Qb4+
169.Ka6 Kf4 170.Qe6 Ke4 171.Qc6+ Ke3
172.Qb5 Qc3 173.c6 Bc7 174.b8R Bxb8
175.Qxf5 Qxc6+ 176.Ka5 Bf4 (3.552.008.815) 2783

51 21:16 -0.90 163...Qa1+ 164.Kb6 Qb2+ 165.Ka6 Qa3+
166.Kb6 Qb4+ 167.Ka6 Kf4 168.Qe6 Ke4
169.Qc6+ Ke3 170.Qb5 Qc3 171.c6 Bc7
172.b8R Bxb8 173.Qxf5 Qxc6+ 174.Ka5 Bf4
175.Kb4 Qb6+ 176.Kc4 Qd4+ (3.552.008.815) 2783

[d]2Q5/1P6/K7/2P1bp2/6k1/q7/8/8 w - -

Engine: Kaissa IV (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

56 41:04 -0.90 164.Kb6 Qb4+ 165.Ka6 Kf4 166.Qe6 Ke4
167.Qc6+ Ke3 168.Qb5 Qc3 169.c6 Bc7
170.b8Q Bxb8 171.Qxf5 Qxc6+ 172.Ka5 Bg3
173.Qg5+ Kf3 174.Qf5+ Kg2 175.Qg4 Qd5+
176.Kb4 Kh2 177.Qe2+ (7.542.234.243) 3059

55 41:04 -0.99 164.Kb5 Qb3+ 165.Ka6 Qc4+ 166.Kb6 Qb4+
167.Ka6 Kf4 168.Qc6 Ke3 169.Qb5 Qa3+
170.Kb6 f4 171.c6 Qd6 172.Qb3+ Kf2
173.Qa2+ Kg3 174.Qg8+ Kh2 175.Qh7+ Kg1
176.Qg8+ Kf1 177.Qb3 (7.542.234.243) 3059

But White probably already lost!? Because if you go forward again (without any tablebases in use here)


[d]2Q5/1P6/K7/2P1bp2/1q4k1/8/8/8 b - -

Engine: Kaissa IV (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

44 3:56 -2.14 165...Qa4+ 166.Kb6 Qb4+ 167.Ka6 Kf4
168.Qe6 Ke4 169.Qc6+ Ke3 170.Qb5 Qa3+
171.Kb6 f4 172.c6 Qd6 173.Qb3+ Kf2
174.Qc2+ Kf3 175.Qc4 Kg2 176.Qc2+ Kh3
177.Qh7+ Kg3 178.Qg8+ Kh4 (655.500.694) 2776

44 3:56 -2.06 165...Kf4 166.Qe6 Ke4 167.Qc6+ Ke3
168.Qb5 Qc3 169.c6 f4 170.Ka7 Qa3+
171.Kb6 Qd6 172.Qb3+ Kf2 173.Qc2+ Kf3
174.Qc4 Kg2 175.Qc2+ Kh3 176.Qh7+ Kg3
177.Qg8+ Kh4 178.Qh7+ Kg5 (655.500.694) 2776
______________________________________________________
.
.
50 18:01 -2.56 165...Qa4+ 166.Kb6 Qb4+ 167.Ka6 Kf4
168.Qc6 Ke3 169.Qb5 Qa3+ 170.Kb6 f4
171.c6 Qd6 172.Qb3+ Kf2 173.Qc2+ Kg1
174.Qb1+ Kg2 175.Qc2+ Kh3 176.Qh7+ Kg3
177.Qg8+ Kh4 178.Qc4 Kg5 (3.431.517.355) 3171

50 18:01 -2.55 165...Kf4 166.Qc6 Ke3 167.Qb5 Qa3+
168.Kb6 f4 169.c6 Qd6 170.Qb3+ Ke2
171.Qc2+ Kf1 172.Qb1+ Kg2 173.Qc2+ Kh3
174.Qh7+ Kg3 175.Qg8+ Kh4 176.Qc4 Kg5
177.Ka7 Qe7 178.Qg8+ Kh6 (3.431.517.355) 3171
______________________________________________________

51 22:02 -2.85 165...Kf4 166.Qc6 Ke3 167.Qb5 Qa3+
168.Kb6 f4 169.c6 Qd6 170.Qb3+ Kf2
171.Qc2+ Kg1 172.Qc1+ Kg2 173.Qc2+ Kh3
174.Qb3+ Kh4 175.Qc4 Kg5 176.Qg8+ Kh6
177.Qc4 Qf6 178.Qg8 Qe7 (4.074.865.789) 3081

51 22:02 -2.74 165...Qa4+ 166.Kb6 Qb4+ 167.Ka6 Kf4
168.Qc6 Ke3 169.Qb5 Qa3+ 170.Kb6 f4
171.c6 Qd6 172.Qb3+ Kf2 173.Qc2+ Kg1
174.Qc1+ Kg2 175.Qc2+ Kh3 176.Qb3+ Kh4
177.Qc4 Kg5 178.Qg8+ Kh6 (4.074.865.789) 3081

[Eelco de Groot]

Now at -3 but of course it is better to look at it with tablebases, the more so if you don't trust the standard evaluation.

2Q5/1P6/K7/2P1bp2/1q4k1/8/8/8 b - -

Engine: Kaissa IV (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

55 81:06 -3.02 165...Kf4 166.Qe6 Ke4 167.Qc6+ Ke3
168.Qb5 Qc3 169.c6 f4 170.Ka7 Qa3+
171.Kb6 Qd6 172.Qb3+ Kf2 173.Qa2+ Kg3
174.Qg8+ Kh4 175.Qc4 Kg5 176.Qg8+ Kh6
177.Qc4 Qf6 178.Qg8 Qe7 (18.286.922.318) 3757

55 81:06 -3.01 165...Qa4+ 166.Kb6 Qb4+ 167.Ka6 Kf4
168.Qe6 Ke4 169.Qc6+ Ke3 170.Qb5 Qc3
171.c6 f4 172.Ka7 Qa3+ 173.Kb6 Qd6
174.Qb3+ Kf2 175.Qc2+ Kg1 176.Qb1+ Kg2
177.Qc2+ Kh3 178.Qb3+ Kh4 (18.286.922.318) 3757

[Spliffjiffer]

hi Eelco, yes the line your Kaissa gives is practically the same i was getting my conclusion from (but as sayed i have the most important 6-men installed)...your Kaissa gives:
55 81:06 -3.02 165...Kf4 166.Qe6 Ke4 167.Qc6+ Ke3
168.Qb5 Qc3 169.c6 f4 170.Ka7 Qa3+
171.Kb6 Qd6 172.Qb3+ Kf2 173.Qa2+ Kg3
174.Qg8+ Kh4 175.Qc4 Kg5
according to my quick analysis this is indeed winning but quickly after i checked this out i found 175.Qh7+ (instead of 175.Qc4??!) which is leading to a forced repetition i think (i did not anylyse very deep so i dont really KNOW why its 0.00 for SF)

regards

[zullil]

[d]2Q5/1P6/K7/2Pqbp2/6k1/8/8/8 w - - 29 168

Cfish-dev with 6-man endgame tables says 168. Ka7 draws and all other moves lose.

After 168. Ka7 Kg5 we have

[d]2Q5/KP6/8/2Pqbpk1/8/8/8/8 w - - 31 169

and all moves lose except for one cute one.

[Spliffjiffer]

yes, its incredible ....1. its a study...2...sometimes the engines are insanely amazing, othertimes they dont get the easiest things

[George Tsavdaris]

After 168. Ka7 Kg5 we have

[d]2Q5/KP6/8/2Pqbpk1/8/8/8/8 w - - 31 169

and all moves lose except for one cute one.

Yes b8N!! draws.
[d]1NQ5/K7/8/2Pqbpk1/8/8/8/8 b - - 0 169


Problem is that after 168.Ka7 black instead of 168...Kg5 can play 168...Qa2+
And then after the forced: 169.Kb6 Qb3+ 170.Ka6 Qa4+ 171.Kb6 Qb4+ 172.Ka6 Kf4 and is this a draw? Maybe.

[d]2Q5/1P6/K7/2P1bp2/1q3k2/8/8/8 w - - 0 173

Note that now 173.Qc6 or Qe6 doesn't matter as they lead to transposition. This is forced:
E.g 173.Qc6 Ke3 174.Qb5 Qc3 175.c6 f4 176.Ka7 Qa3+ 177.Kb6 Qd6 178.Qb3+ Kf2 179.Qa2+ and this is a win for black? Hmm....
Can you find a better move for white in the above line?
[d]8/1P6/1KPq4/4b3/5p2/8/Q4k2/8 b - - 0 179



Note, that white missed the draw even earlier than 168th move and instead of 160.Qf8 he could have drawn with 160.Qh7+ Kg4 161.b8N!!

[d]1N6/K6Q/4q3/2P1bp2/6k1/8/8/8 b - - 0 161

[George Tsavdaris]

Problem is that after 168.Ka7 black instead of 168...Kg5 can play 168...Qa2+
And then after the forced: 169.Kb6 Qb3+ 170.Ka6 Qa4+ 171.Kb6 Qb4+ 172.Ka6 Kf4 and is this a draw? Maybe.

[d]2Q5/1P6/K7/2P1bp2/1q3k2/8/8/8 w - - 0 173

I got someone on Leela's discord(Aloril) with full 7 TBs on SSDs with Cfish to analyze this after 168.Ka7 Qa2+ 169. Kb6 Qb3+ and got:
info depth 47 seldepth 16 multipv 1 score cp 0 nodes 274397857 nps 3839450 hashfull 101 tbhits 9064229 time 71468 pv b6c6 g4f4 c8d8 f4e4 d8d2 b3e6 c6b5 f5f4 d2d1 f4f3 d1b1 e4f4 b1c1 f4f5 c1d1

So it must be a draw.

Note that now 173.Qc6 or Qe6 doesn't matter as they lead to transposition. This is forced:
E.g 173.Qc6 Ke3 174.Qb5 Qc3 175.c6 f4 176.Ka7 Qa3+ 177.Kb6 Qd6 178.Qb3+ Kf2 179.Qa2+ and this is a win for black? Hmm....

And he analyzed it on this also:
info depth 64 seldepth 7 multipv 1 score cp 0 nodes 2215832333 nps 3049745 hashfull 592 tbhits 78924206 time 726563 pv f2g3 a2g8 g3h4 g8h7 h4g5 h7g8

So again draw.

So Fire had two ways to draw this, with 168.Ka7 instead of 168.Kb6? and with the more easy way i've shown instead of playing 160.Qf8(that still draws) that he played, he could have drawn with 160.Qh7+ Kg4 161.b8N!!

[IanO]

Speaking of interesting endgames, I found this gem in the Fritz-Ethereal game.

[d]8/5B2/8/B2n1P2/3n2Pb/p7/4k3/1K6 b - - 1 70
The key 70...Bd8!! was a bolt from the blue!