Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. O-O Bd6 6. d4 Bg4 7. dxe5 Bxf3 8.
Qxf3 Bxe5 9. c3 Ne7 10. Be3 O-O 11. Rd1 Qc8 12. Nd2 b6 13. Nc4 Ng6 14. Qf5 Re8
15. Qxc8 Raxc8 16. Rd7 Bf4 17. Bxf4 Nxf4 18. f3 Ng6 19. Rad1 h6 20. Kf2 Nf8 21.
R7d4 Ne6 22. R4d2 Rcd8 23. Rxd8 Rxd8 24. Rxd8+ Nxd8 25. Ne5 Kf8 26. Ke3 Ke7 27.
Kd4 Ke6 28. f4 c5+ 29. Kc4 f6 30. Nd3 Nc6 31. g3 *
Position (FEN): 8/2p3p1/ppn1kp1p/2p5/2K1PP2/2PN2P1/PP5P/8 b - - 0 31
Black to move.
Themes:  Endgame, Knight Endgame Mate in 1 
Puzzle rating: 1203
Best move: Na5#