Chess puzzle (Checkmate)
Moves: 1. e4 d5 2. f3 Nc6 3. d4 e5 4. Bb5 a6 5. Ba4 exd4 6. exd5 Qxd5 7. Bf4 Bb4+ 8.
Bd2 Qg5 9. c3 Qxg2 10. Qe2+ Be6 11. Qxg2 dxc3 12. Bxc3 Bd6 13. Qxg7 O-O-O 14.
Qxh8 Nh6 15. Qf6 Bc5 16. Ne2 Ng8 17. Qg7 Be7 18. Qxh7 Nf6 19. Qg7 Nd5 20. Bd4
Ndb4 21. Bf6 Nc2+ 22. Kf1 Rd1+ 23. Kg2 Rxh1 24. Kxh1 Bc5 25. Bxc2 Bd5 26. Qh8+
Kd7 27. Nbc3 *
Position (FEN): 7Q/1ppk1p2/p1n2B2/2bb4/8/2N2P2/PPB1N2P/R6K b - - 4 27
Black to move.
Themes:  Middlegame Double Bishop Mate, Mate in 1 
Puzzle rating: 817
Best move: Bxf3#