Chess puzzle (Checkmate)
Opening: Blackmar-Diemer_Gambit, Blackmar-Diemer_Gambit_Gedult_Gambit
Moves: 1. e4 d5 2. d4 dxe4 3. f3 exf3 4. Nxf3 Nf6 5. Bc4 e6 6. O-O Be7 7. c3 O-O 8.
Bg5 c6 9. Nbd2 b5 10. Bb3 a5 11. Qe2 a4 12. Bc2 Nbd7 13. Rad1 Nb6 14. Ne5 Nbd5
15. Ne4 Nxe4 16. Bxe7 Qxe7 17. Qxe4 Nf6 18. Rxf6 Qxf6 *
Position (FEN): r1b2rk1/5ppp/2p1pq2/1p2N3/p2PQ3/2P5/PPB3PP/3R2K1 w - - 0 19
White to move.
Themes: Kingside Attack Middlegame Mate in 1 
Puzzle rating: 850
Best move: Qxh7#