Chess puzzle (Checkmate)
Moves: 1. d4 Nf6 2. Bf4 g6 3. Nc3 Bg7 4. Qd2 O-O 5. Bh6 d6 6. Bxg7 Kxg7 7. O-O-O Nbd7
8. e4 b6 9. h4 h5 10. f3 Bb7 11. Bd3 Re8 12. g4 e5 13. d5 hxg4 14. fxg4 Nxg4
15. Nf3 Nc5 16. Rdg1 Nxd3+ 17. cxd3 Qd7 18. h5 Rh8 19. hxg6 Rxh1 20. Rxh1 fxg6
21. Ng5 Rh8 22. Ne6+ Kg8 23. Rxh8+ Kxh8 24. Qg5 Nf2 25. Qg3 Nh1 26. Qh3+ Qh7
27. Qxh7+ Kxh7 28. Nxc7 Nf2 29. Kd2 g5 30. Ke2 Nh3 31. Nd1 g4 32. Nf2 Nf4+ 33.
Kf1 g3 34. Nd1 Kh6 35. Nb5 Kh5 36. Nxd6 Ba6 37. Nc4 Bxc4 38. dxc4 Kh4 39. Ne3
Kh3 40. d6 Ne6 41. d7 Nd8 42. b3 a5 43. Kg1 Nc6 44. Nd5 Nd8 45. Nxb6 Nc6 46.
Nc8 g2 47. Ne7 Nd8 48. Ng6 Kg3 49. Nxe5 Ne6 50. Nc6 Nf4 51. Nd4 *
Position (FEN): 8/3P4/8/p7/2PNPn2/1P4k1/P5p1/6K1 b - - 4 51
Black to move.
Themes:  Endgame, Knight Endgame Mate in 1 
Puzzle rating: 1246
Best move: Nh3#