Chess puzzle (Checkmate)
Moves: 1. Nf3 Nf6 2. g3 b6 3. Bg2 Bb7 4. O-O g6 5. c4 Bg7 6. Nc3 O-O 7. d4 e6 8. Qc2
d6 9. e4 Nbd7 10. Re1 e5 11. h3 h6 12. Be3 Re8 13. Rad1 Qc8 14. b3 a6 15. dxe5
dxe5 16. Nd5 Nh7 17. Qd2 Nc5 18. Bxh6 Bxh6 19. Qxh6 b5 20. Ng5 Nxg5 *
Position (FEN): r1q1r1k1/1bp2p2/p5pQ/1pnNp1n1/2P1P3/1P4PP/P4PB1/3RR1K1 w - - 0 21
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 958
Best move: Nf6#