SELECTED CHESS COMPOSITIONS GEORGE GRÄTZER

Transcription

1 SELECTED CHESS COMPOSITIONS GEORGE GRÄTZER 1

2 2 GEORGE GRÄTZER If you done it, it ain t bragging. Baseball great Dizzy Dean 1. Introduction This is the cover of the magazine Magyar Sakkélet (Hungarian Chesslife), the official organ of the Hungarian Chess Federation, from May It records the last chess game I played in a tournament. (I am the youngster on the right side of the picture.)

3 SELECTED CHESS COMPOSITIONS 3 This is how the story starts about my chess compositions. I am a mathematician, and as such I am not used to writing in the first person singular. But if I want the story told, I have to tell it myself. Almost everybody in this story is dead, most long dead. When my picture appeared in the chess magazine, I was about to graduate from grade 12. The team I played for, Tipográfia (Typography), just won the Budapest championship. The leader of our team was asked to write an article for the magazine about our team, so he asked us to look over the games we played in this tournament, and look for positions in which we were clever, so he can write them up. It was a big chore to look over the thirty or so games. The result was extremely disappointing. Even though I rated 85%, every win was due to an error of the opponents. I decided that the time I spend on chess would be more satisfying if I created chess problems these are absolute and not illusory, not dependent on your opponents ignorance and psychology. Dr. Jenő Bán ( ), one of the chess masters at the chess club, introduced us to chess compositions, especially endgames (white plays and wins or draws). I figured that if I compose endgames, and I state that white wins (or draws), these ought to be absolute, and not dependent on mistakes by the opponent. I started studying endgames; you have to be familiar with thousands of them to create original ones. My second mentor was György Páros ( ). Unquestionably the world leading chess composer in helpmates. 1 He taught me how to aim at uncluttered positions, few pieces, and elegant ideas. Páros told me the story of one of his most famous compositions; how he struggled with the idea for years, and how he woke up one morning and set up the position on his chess board. And that is why I quit after about two years. The subconscious work necessary for success in chess compositions competed against the same for mathematical research, and I had to give one of them up. I look back at this period, , with great satisfaction. For this time period, my endgame #11 was officially placed the second best in Hungary which is not bad because I was so young and just starting. And the one placed first proved to be defective! Acknowledgement. Having moved in the last 50 years to two new countries, it is not surprising that I have no record of my chess compositions. Mária Halmos did all the work to find them, and I do believe that she found most of them. János Mikitovics (JM) the author of the splendid Website: Hungarian Chess Composers: went through my compositions and sent me a long document, analyzing them. He also took the time to educate me about the technical advances that have happened, especially, Fritz (I now have version 11) and the Knowledge4IT Website. Another huge advance is the Nalimov endgame databases, now complete up to 5 pieces (consider that my Composition #1 had only 5 pieces), and covering all the 6 piece positions without pawns. 1 In a helpmate both sides are cooperating to checkmate black. The first move is made by black. So in a helpmate in two, black moves, then white moves, then black moves again, and finally white checkmates black.

4 4 GEORGE GRÄTZER 2. Picking favorites I agree with MJ. If you want to see only three chess compositions of mine, pick the endgames No. 1b, No. 11 and the helpmate No. 13.

5 SELECTED CHESS COMPOSITIONS 5 3. Chronological listing 1a Hungarian National Endgame Competition Sixth place Magyar Sakkélet 1954, issue 11/12, p. 285 (revised) White draws This was my first endgame composition; I was 18. It was published in 1954 in Magyar Sakkélet, so it participated in the 1954 Hungarian National Endgame Competition, placing sixth.

6 6 GEORGE GRÄTZER Solution (Magyar Sakkélet 1954, issue 11/12, p. 285): 1.Kg6!(1. g4? d5 2. g5 d4 3. g6 d3 4. g7 Bc4 black wins) 1., d5 2. Kf5 d4 3. Nd7! (3. Ke4? d3 4. Ke3 Ke1 black wins) 3., d3 4. Nb6! (4. Nf6? Bc6 black wins) 4., d2 5. Nd5 Ke2 6. Nc3+ (6. Kf4? Bc6 7. Nc3+ Kd3 8. Nd1 Bg2: black wins) 6., Kd3 7. Ne4! d1q 8. Nf2+ draw. 5., Kg2: 6. Nc3, Kf3 7. Ke5 Ba4 8. Kd4 Bc2 9. Nd1 Ke2 10. Nb2 draw

7 SELECTED CHESS COMPOSITIONS 7 1b. OTSB Nyeviczkey Memorial Competition First prize (revised) Magyar Sakkélet 1956, issue 11/12 White draws Two years later, I composed this endgame. This leads to the opening position of 1a, when in move 6 black appears to capture the white knight with Bb5.

8 8 GEORGE GRÄTZER Solution (Magyar Sakkélet 1956, issue 11/12): 1. b7 Rh4+ 2. Kg7 Rg4+ 3. Kh8: Rg8+ 4. Kh7 Bc4 5. b8q Rb8: 6. Nb8: Bb5 now continue as in #1, white draws.

9 SELECTED CHESS COMPOSITIONS 9 2a. OTSB 1954 Hungarian National Endgame Competition (revised) Second HM Magyar Sakkélet 1954, issue 12, #82 White wins 2b. White wins

10 10 GEORGE GRÄTZER Solution 2a (Magyar Sakkélet 1955, issue 3): 1. Bh4:+!! (1. Bc7+? d6!! 2. Rg8 Kf2 3. Rf8 Ke1 4. Rg8 e2 5. Ba5 Kd1 or 1. Rb8 e2 2. Ba5 h3 white cannot win;) 1., Kh4: 2. Rh6+, Kg3 3. Rh1, Kg2 4. Rb1!, Kf2 5. Kd3, e2 6. Kd2, Kf3 7. Re1!, d6 8. Rg1!, Kf2 9. Rb1!, Kf3 10. Re1, d5 11. Rg1!, Kf2 12. Rb1!, Kf3 13. Re1, d4 14. Rg1!, Kf2 15. Rb1!, Kf Re1, d3 17. Kd3:, Kf2 18. Kd2, Kf3 19. Rg1, Kf2 20. Rb1, Kf3 21. Re1 and so on, white wins. Solution 2b Same as that of 2a, starting with move 2.

11 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1955, issue 1, #90 White wins

12 12 GEORGE GRÄTZER Solution (Magyar Sakkélet 1955, issue 4): 1. cb6:, Rb6: 2. Qd8+, Ka7 3. Qd4!, g5 4. Kg2!, g4! 5. Kg1!, f3 6. Kf2, h3 7. Kg3 and so on, white wins.

13 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1955, issue 4, #1863 Helpmate in 3 (version) a. The diagram b. Move white pawn from b3 to g5

14 14 GEORGE GRÄTZER Solution (Magyar Sakkélet 1955, issue 6): a. 1. Nb4:, g8n 2.Nc6, b4! 3. Nd8, Ne7 checkmate. b. 1. Bc1, g8b 2. Bg5:, Bf7! 3. Bd8, Be6 checkmate.

15 SELECTED CHESS COMPOSITIONS 15 5a. Magyar Sakkélet 1955, issue 5, #105 (revised) White wins 5b. Magyar Sakkélet 1955, issue 5, #106 (revised) BTSB 1956 International Endgame Competition Fourth prize Magyar Sakkélet 1956, issue 11/12, #106 White wins

16 16 GEORGE GRÄTZER Solution 5a (Magyar Sakkélet 1955, issue 8): 1. a6 h3 2. Nf3! (2. a7? Bd5: 3. Kd5: h2 4. a8q h1q+ 5. f3 Qe1: 6. Ke5: Qg3+ 7. Kf5 Qf4+ 8. Kg6 Kf2 9. Qe4 Kg3 10. Kh5 Kg2! 11. Qf4: gf4: 12. g5 Kf3: draw.) 2. Kf3: 3. a7 Bd5 4. Kd5: h2 5. Ke5:! Kg5: 6. a8b! white wins. (6. a8q? h1q 7. Ke5: Kg4: 8. Qh1: stalemate.) Solution 5b: 1. Nc3 (1. a7? Bd4 2. Bb6: Bh8 3. Bc7 a3 4. Bd5 Bd5: 5. Kd5: a2 6. h8q a!q+ 7. f3 easy draw) 1., Kc3 2. h7, Bd4 3. Bb6: Bh8 4. Bc7! (4. Bd8 a3 5. Bf6+ Bf6: 6. Kf6: a2 7. h8q a1q 8, Ke6+ d4 easy draw) 4., a3 5. Bc7! a3 5. Be5+ Be5: 6. Ke5: h8b! white wins.

17 SELECTED CHESS COMPOSITIONS With P. Bauer BTSB 1956 International Endgame Competition Nineth place Magyar Sakkélet 1955, issue 6, # 116 White wins

18 18 GEORGE GRÄTZER Solution (Magyar Sakkélet 1955, issue 9): 1. Re2 d3 2. e7! d2! 3. Rd2: Re6 4. Rd7+ Kb6 5. Kc3! (5. Rd6? Kb5: 6. Re6: stalemate; 5. Kc4? Re7: 6. Re7: stalemate) 5. Kb5 6. Kd4 Kc6 7. Ra7 Re1 (7. Kb6 8. Kd5 Re1 9. Rd7 wins) 8. b5+ Kb5: 9. Kd5 Kb6 10. Rd7 Rd Ke6 Re Kf7 Rf Ke8 and Kd8 wins.

19 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1955, issue 7, #1933 Mate in 45

20 20 GEORGE GRÄTZER Solution (Magyar Sakkélet 1955, issue 10): 1. Na3+ Ka1 2. Nb1! Kb1: 3. Qd3+ Ka1 4. Qd4 Kb1 5. Qe4+ Ka1 6. Qe5 Kb1 7. Qf5+ Ka1 8. Qf6 Kb1 9. Qg6+ Ka1 10. Qg7 Kb1 11. Qh7+ Ka1 12. Qh8 Ka1 13. Qg7 Kb1 14. Qh7+ Ka1 15. Qh8 a6 16. Qg7 Kb1 17. Qh7+ Ka1 18. Qh8 a5 19. Qg7 Kb1 20. Qh7+ Ka1 21. Qh8 a4 22. Qg7 Kb1 23. Qh7+ Ka1 24. Qh8 a3 25. Qg7 Kb1 26. Qh7+ Ka1 27. Qh8 b5 28. Qg7 Kb1 29. Qh7+ Ka1 30. Qh8 b4 31. Qg7 Kb1 32. Qh7 Ka1 33. Qh8 e1q+ 34. Ke1: Kb1 35. Qh7+ Kc1 36. Qh6+ Kb1 37. Qg6+ Kc1 38. Qg5+ Kb1 39. Qf5+ Kc1 40. Qf4+ Kb1 41. Qe4+ Kc1 42. Qe3+ Kb1 43. Qd3+ Ka1 44. Kd4 Kb1 45. Qd1+ checkmate.

21 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1955, issue 10, #1989 Mate in 4

22 22 GEORGE GRÄTZER Solution (Magyar Sakkélet 1956, issue 1): 1. g7! threats: 2. Qg6 checkmate and 2. gh8:q checkmate. 1. Rhe8: 2. g8n+ Rg8: 3. Nf6 checkmate in the next move. 1. Rce8: 2. gh:q+ Rh8: 3. Ng7 checkmate in the next move.

23 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1955, issue 11, #2037 Helpmate in 2 On October 6, 1955, Gyula Neukomm organized a composition with a theme quick tournament. Time limit for creating the composition: 2 hours; time limit for judging: 1 hour. The theme: Helpmate in 2, and in the first move, the black queen takes the white queen. If the white queen (on e7) is removed or replaced by another piece, the composition is incorrect; least obvious is the replacement with a rook, in which case, the unintended solution is 1. Kd5: Bf3+ 2. Kd6: Bb4 checkmate.

24 24 GEORGE GRÄTZER Solution (Magyar Sakkélet 1955, issue 11): 1. Qe7: Kg2 2. Nd3 Bf3 checkmate.

25 SELECTED CHESS COMPOSITIONS Competition of the Finnish Federation of Chess Composers Sixth place Magyar Sakkélet 1956, issue 3, #189 White wins

26 26 GEORGE GRÄTZER Solution (Magyar Sakkélet 1956, issue 3): 1. c4! Bc4: (1. Rd1 or f1 2. Ne3+ white wins. 1. Ra5 2. f7 Rf5 3. Ne3+ white wins) 2. Ne3+ Kb3 3. Nc4: Kc4: 4. Bf3! Ra5 (4. Rf1 or a6 5. Be2+ white wins. 4. Rb1 or a2 5. Be2+ and 6. f7 wins.) 5. Bg4 white wins.

27 SELECTED CHESS COMPOSITIONS Népszava First prize Magyar Sakkélet 1956, issue 3, #186 Fourth Hungarian National Competition Second prize Magyar Sakkélet 1957, issue 8/9, #242 White draws

28 28 GEORGE GRÄTZER Solution (Magyar Sakkélet 1956, issue 3): 1. Na4+ Kb4 or b5 (1. Kd5 2. Nb6+ Ke5 3. Nd7+ and so on perpetual check or return to the main variant) 2. Rb6+ Ka4: 3. Bd7+ Nc6 4. Bc6:+ Ka5! (4. Qc6: 5. Rc6 and 6. Rc1 draw.) 5. Rb5+! (5. Bg2:? Kb6:! 6. Bd5 Kc5! black wins.) 5. Ka6 6. Bg2: Kb5: 7. Bf1!! Kb4 8. Kc2 draw. 6. a2 7. Rc5!! a1q 8. Bh3: Qd1+ 9. Kc4 Qc Kb4 Qb Kc4 Qe Kb3! draw (12. Kb4? Qe7! 13. Kc4 Qh4+ black wins). Similarly 9. Qc Kb4 Qf Kb3! draw.

29 SELECTED CHESS COMPOSITIONS OTSB 1956 Second prize Magyar Sakkélet 1956, issue 7, #2155 Helpmate in 3 Solution: 1. Kf5 d8b 2. Ke6 e8r 3. Kd7 b8n checkmate.

30 30 GEORGE GRÄTZER 13. Magyar Sakkélet 1957, issue 5, #236 White draws Solution (Magyar Sakkélet 1957, issue 10): 1. e7! (1. b3? a3 2. e7. Rg3:+! 3. Kg3: Bg6: black wins. 1. g7? Rd8 black wins.) 1. Re3 2. g7 Ba2 3. b3! Bb3: 4. e4! Be4: 5. Ne6! Be6:! 6. e8q Bg4: 7. Kh4! Re8: 8. g8q Rg8: stalemate.

31 SELECTED CHESS COMPOSITIONS Magyar Sakkélet 1957, issue 6, #242 White wins Solution (Magyar Sakkélet 1957, issue 10): 1. b5+! Kb5: 2. de:! (2. Be2+? Kc5 3. de: Rh3+ and 4. Re3 draw.) 2. Ne7: 3. Be2+ Kc5! 4. Ne7: Rh3+ 5. Ka2! (5. Ka4? Rh4+ and 5. Re4 draw.) 5. Be3 6. b4+! and 7. Hd5 (f5)+ wins. (1. de:? Ne7: 2. Be2+ Kb7! 3. Ne7: Rh3+ and 4. Re3 draw. 1. Ne7:? Ne5! 2. Be2+ Kb6 3. Ka4 Rh1 draw.)

32 32 GEORGE GRÄTZER 15. Magyar Sakkélet 1957, issue 12, #257 White wins Solution (Magyar Sakkélet 1958, issue 1): 1. Re4! (1. Ng1:? Bh4: draw.) 1. Nf3:! (1. Nh3: 2. Re1:+ Ka2 3. Kc3: Nf4 4. Rdl white wins.) 2. Ng1! Ng1: 3. Re1:+ Ka2 4. Re3! (4. Rg1:? stalemate) 4. Ka1 5. Bc3:! (5. Kc3:? Kb1 draw.) 5. Ka2 (5. a2 6. Re3! white wins.) 6. Re3 c3! 7. Kc3:! Kbl 8. Kb3! white wins.

33 SELECTED CHESS COMPOSITIONS Cooks and comments 1a. This endgame was published without the white pawn on g2. Cook: 2 1. Kg6 d5 2. Kf5 d4 3. Nd7! d3 4. Nb6 d2 5. Nd5 Ke2! 6. Nc3+ Ke3! and black wins. This position, of course, today is part of the Nalimov database. JM observed that placing a white pawn on g2 eliminates the Cook. 1b. Because of the Cook for 1a, this also had to be revised. Just placing a white pawn on g2 introduces a Cook. There are many ways to go around it, I show two. 2. Originally, this was published in the form: White wins Cook: 1. Rg6+! Kf3 (1., Kf2 2. Bxh4+ Ke2; 2., Kf1 3. Rb6 Ke2 4. Be7 Kd1 5. Bxa3 e2 6. Rxb2+-) 2. Rg1 Kd2 3. Kc4 Kc2 (4., d5+ 5. Kb3+-) 5. Rg2+ e2 (5., Kd1 6.Kc3+-) 6. Rxe2+ Kd1 7. Re1+ Kc2 8. Kb4 b1q+9. Rxb1 Kxb1 10. Kxa3 white wins. Easiest correction: drop the first move, see 2b. Alternatively, block the rook s access to the g file, as is done in 2a. This solution has the added advantage that in 2a the check on c7 seems very attractive. 2 A Cook or Cook solution is an alternative way of achieving the goal, demonstrating that the composition is flawed.

34 34 GEORGE GRÄTZER This endgame shows some limitations of even the best chess programs. Look at this position in this endgame: White wins Even with unlimited time, Fritz 11 does not find the winning move: Rb1. Nor does Sigma Chess with HIARCS 12.1 MP. Apparently, this type of zugzwang 3 is difficult for a computer program to analyze. 3 A situation in a chess game in which a player is forced to make an undesirable or disadvantageous move.

35 SELECTED CHESS COMPOSITIONS Originally, 5a was published without the c2 pawn. Cook (JM): 1. a6 Bb1! 2. Kxe5 h3 3. a7 Be4 4. Kxe4 h2 5. a8q h1q+ 6. f3 Qxe1 7. Kf5 Qd2 8. Qe4+ Kf1 9. f4 Qd7+ draw. 5b is derived from its published form: White draws Solution (Magyar Sakkélet 1955, issue 8): 1. Bb8 Bg1 2. Be5 Bd4 3. Bd4: Kd4: 4. h6 Nf6 5. Kf6: a2 6. h7 a1q 7. h8q Ke5+ 8. Kg5: Qh8 stalemate. If 6. a1b 7. h8q Ke4:+ 8. Kf7:! Bh8 9. Kg6 draw. 1. a2 2. Be5 Bg3: 3. Ba1 Bf2 4. h6 Bd4 5. Bd4: Kd4: 6. h7 a1q 7. h8q+ f6 8. Qe8: Ke4 9. Qg6+ and 10. Qf5 draw. (1. h6? Nf6 2. Kf6: a2 3. Bd4 Kd4: 4. h7 a1q 5. h8q Ke4: 6. Kg5: Qe5+! black wins.) Cook: (JM) 1 Nf6! 2. Kxf6 a2 3. Be5 Bxg3 4. Ba1 Bf2! (4. Be1? 5. h6 Bc3+ 6. Bxc3 Kxc3 7. h7 a1q 8. h8q Kd3+ 9. e5 Qf Ke7 Qf4 11. Qf6 Qxg4 12. Kxf7 Qh5+) 5. h6 Bd4+ 6.Bxd4 Kxd4 7. h7 Kxe4 (7. a1q 8. h8q Kxe4+ 9. Kxg5 Qxh8 stalemate.) 8. Kxg5 a1b!! Black wins. (8. a1q? 9. h8q! Qxh8 stalemate.)

36 36 GEORGE GRÄTZER 10. Cooks: 1. Ra4, Bd2 2. Rd4, Nc3 checkmate 1. Ng5, Nxf6+ 2. Kf4 Qxe5 checkmate Lucky for me, these were not discovered in the one hour Mr. Neukomm had to find cooks. 11. My #11 received the second prize in the Fourth Hungarian National Competition. The first prize winner was A. Korányi s endgame: White wins Solution (Magyar Sakkélet 1957, issue 8/9, p. 139): 1. c6 Nb3 2. Bc5+ Nc5: 3. c7 Rb1+ 4. Ke2 Rb2+ 5. Kf1 Rb1+ 6. Kg2 Rb2+ 7. Kh3 Rb3+ 8. Kh4: g5+ 9. Kg4 Rb Kf5 Rf Kg6 Rf Kf6: Nd Ke6 Nb6 14. Bg4 Nc8 15. Kf6 Ne7 16. Kg5: Kg8 17. Bc6+ Kg7 18. Bc4 (b3) Nc8 19. Bb3 (c4) Ne7 20. Bc6 Kf8 21. Kf6 Ke8 22. Kg7 white wins.

37 SELECTED CHESS COMPOSITIONS 37 The final position is an interesting zugzwang. 4 Of course, it is not this position that makes Korányi s work so remarkable, but the 22 interesting moves that lead up to it. It is difficult to use Fritz 11 or Hiarcs 12.1 MP to find a Cook in this composition. To look ahead 22 moves is a horizon too far. However, we can observe that in move 12. Kf6: reduces the number of pieces to 6: so we can use the Knowledge4IT Website. Obviously, black moves Nf7+, and here is the surprise: 13. Ke6 wins in 19 moves and 13. Kf5 also wins in 19 moves. 13. Ke6 is the intended solution (see above); 13. Kf5 is a Cook: 13. Nb6 14. Ke6 (14. Ke5 also wins.) Nc8 15. Ke5 Na7 16. Kd5 Nc8 17. Bg4 Ne7 18. Kd6 Kf7 19. Kd7 Kf6 20. Ke8 white wins. 4 A situation in a chess game in which a player is forced to make an undesirable or disadvantageous move.

38 38 GEORGE GRÄTZER 5. From the ashes... From the defective compositions of old, we are trying tyo resurrect some with János Mikitovics. 16. George Grätzer & János Mikitovics MatPlus, May 2009 White wins Solution: 1. Kb7!/i Ne8 2. a7!/ii Nc7 3. Nb3! Kd6/iii=main 4. Nc5!/iv Na8 5. Ne4+!/v Kd7 6. Ng5!!/vi 6...f5/vii=main 7. Nxe6 wins. i) 1. a7?? Kc8! 2. Nc2 Ne8 3. Nd4 Nc7#; 1. Kb8? Ne8! 2. a7 Nc7= ii) 2.Nb3? Nd6+= iii) main 3...Na8 4. Nc5+ Kd6 (4...Kd8 5. Ne4! f5 6. Ng5 Kd7 7. Nxe6+-) 5. Ne4+ (5. Na6? Kd7 6. Nb8+ Kd6 7. Nc6 f5! 8. Ne5 Nc7 9. Nc4+ Kd7 10. Ne5+ Kd6 11. Nc4+ Kd7 12. Ne5+ Kd6 positional draw.) 5...Kd7 6. Ng5+main line; 3...e5 4. Nc5+ Kd8 5. Kc6+- (5. Na6? Na8 6. Nb8 f6! 7. Nc6+ Kd7=) iv) Thematic try 4. Nd4? Na8 (4...Kd7? 5. Nf3 f6 6. Nd2 f5 7. Nb3 e5 8. Nc5+ Kd8 9. Ne6+ Nxe6 10. a8q++-; 4...e5 5. Nb5+ Nxb5) 5. Kxa8 (5. Nc6 f5 (5...f6 6. Nd4) 6. Ne5) 5...Kc7!= v) Thematic try 5. Na6? Kd7! 6. Nb8+ Kd6 7. Nc6 f5 8. Ne5 Nc7 (8.. f4? 9. Nc4+ Kd5 10. Kxa8+-) 9. Nf7+ (9. Ng6 Na8! (9.. e5? 10. Ne7! f4 11. Nd5+-) 10. Nf4 e5 11. Nd5 e4=) 9.. Kd7 10. Ng5 e5!= (10.. Kd6? 11. Nxe6+-) ; 5. Na4? f5 6. Nb6 Nc7 7. Nc4+ Kd7 8. Ne5+ Kd6 (8.. Kd8? 9. Nc6+ Kd7 10. Nd4 e5 11. Nxf5+-)9. Nc6 Na8 10. Nd8 f4= (10.. Nc7? 11. Nxe6+-) vi) Thematic try 6. Nf6+?! Kd6! (6.. Kd8? 7. Nh7!! e5 8. Nf6 Nc7 9. Ne8! Na8 10. Nd6! f6 11. Kc6!! (11. Ne4?! f5 12. Nd6 f4! (12.. e4? 13. Nxf5+-) 13. Nf7+ Ke7!! (13.. Kd7? 14. Nxe5++-) 14. Kxa8 f3=) 11.. Nc7 12. Ne8! Na8 13. Nxf6!+-) 7. Ne8+ Kd7 8. Kxa8 Kc8 9. Nd6+ Kc7 10. Nxf7 Kc8 11. Ne5 Kc7 positional draw. vii) main 6.. e5 7. Nxf7 a) 7. Ne4? f5= (7.. Nc7? 8. Nf6+ Kd6 9. Ne8+ Nxe8 10. a8q+-); b) 7. Nf3? f6 8. Nd2 f5 (8.. Nc7? 9. Ne4 f5 10. Nc5+ Kd8 11. Ne6+ Nxe6 12. a8q++-; 8.. Kd8? 9. Ne4 f5 10. Nd6 f4 11. Nf7++-) 9. Nc4 e4 10. Nb6+ Kd6 11. Nxa8 e3 12. Nc7 e2 13. a8q e1q 14. Qa3+ (14. Qd8+ Kc5 15. Qd5+ Kb4 16. Qb5+ Ka3= (16.. Kc3? 17. Qa5++-) ) 14.. Kd7 (14.. Ke5? 15. Qe7++-)15. Qa4+ Kd8=; 7.. e4 8. Ne5++- (8. Ng5? e3=) K7/3k1ps1/P3p3/8/8/8/8/S7 Ka8 Sa1 Pa6 - Kd7 Sg7 Pe6 f7