Chess puzzle (Checkmate)
Moves: 1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Nf3 Bg7 5. Bc4 O-O 6. Be3 Nbd7 7. h4 c6 8. Bb3
b5 9. a3 a5 10. e5 dxe5 11. dxe5 Ng4 12. e6 Ndf6 13. Qxd8 Rxd8 14. exf7+ Kf8
15. Bg5 h6 16. Be3 Nxe3 17. fxe3 a4 18. Ba2 Bf5 19. Ne5 Bxc2 20. e4 Nxe4 *
Position (FEN): r2r1k2/4pPb1/2p3pp/1p2N3/p3n2P/P1N5/BPb3P1/R3K2R w KQ - 0 21
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 1020
Best move: Nxg6#