Chess puzzle (Checkmate)
Moves: 1. d4 d5 2. c4 e6 3. Nc3 c6 4. Nf3 dxc4 5. e4 b5 6. e5 Bb7 7. Be2 a6 8. O-O Ne7
9. Be3 Nd5 10. Nxd5 cxd5 11. Rc1 Be7 12. Qc2 O-O 13. Kh1 Nd7 14. Ng1 Nb6 15. f4
f5 16. g4 g6 17. gxf5 gxf5 18. Nh3 Kh8 19. Rg1 Rg8 20. Ng5 Qd7 *
Position (FEN): r5rk/1b1qb2p/pn2p3/1p1pPpN1/2pP1P2/4B3/PPQ1B2P/2R3RK w - - 6 21
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 622
Best move: Nf7#