Chess puzzle (Checkmate)
Moves: 1. d4 d5 2. Bf4 Nc6 3. a3 Nf6 4. h3 e6 5. e3 Ne4 6. Nd2 Nf6 7. Ngf3 Bd6 8. Bg5
h6 9. Bxf6 gxf6 10. Bb5 Bd7 11. Nh4 Qe7 12. Qf3 O-O-O 13. Nb3 e5 14. Qxd5 exd4
15. Nxd4 Nxd4 16. Bxd7+ Rxd7 17. Qxd4 Be5 18. Qxa7 c6 19. Qa8+ Bb8 20. O-O Qe5
21. c3 *
Position (FEN): Qbk4r/1p1r1p2/2p2p1p/4q3/7N/P1P1P2P/1P3PP1/R4RK1 b - - 0 21
Black to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 750
Best move: Qh2#