Chess puzzle (Crushing)
Moves: 1. e4 e5 2. d3 Nf6 3. f4 d6 4. f5 d5 5. g4 dxe4 6. g5 Nfd7 7. dxe4 Be7 8. h4 b6
9. Bb5 Bb7 10. Bxd7+ Nxd7 11. Nc3 f6 12. Nf3 fxg5 13. Bxg5 Bxg5 14. hxg5 Nf8
15. Qxd8+ Rxd8 16. Nxe5 Rd4 17. Nf3 Bxe4 18. Nxd4 Bxh1 19. O-O-O Bb7 20. Ncb5
g6 21. Re1+ Kd8 22. Nxa7 gxf5 23. Nxf5 Rg8 24. Rg1 c6 25. Nd6 Kc7 26. Rd1 Kb8
27. Nab5 cxb5 28. Nxb5 Ng6 29. Rd6 Kc8 30. Na7+ Kc7 31. Nb5+ Kc8 32. Na7+ Kc7
33. Nb5+ Kb8 34. Rxb6 Ne5 35. Nd6 Rg7 36. Rb5 Nf3 37. Rb3 Nxg5 38. Rg3 h6 39.
Rb3 Rd7 40. Rb6 Ka7 41. Rxb7+ Rxb7 42. Nxb7 Kxb7 43. Kd2 Kc7 44. Ke2 Kd7 45.
Kf2 Ke7 46. Kg3 Kf6 47. Kg4 Kg6 48. a4 h5+ 49. Kh4 Ne4 50. b4 Nc3 *
Position (FEN): 8/8/6k1/7p/PP5K/2n5/2P5/8 w - - 1 51
White to move.
Themes: Defensive Move Endgame, Knight Endgame  
Puzzle rating: 999
Best move: a5