Chess puzzle (Checkmate)
Opening: Nimzowitsch_Defense, Nimzowitsch_Defense_Declined_Variation
Moves: 1. e4 Nc6 2. Nf3 g6 3. d4 Bg7 4. c3 d5 5. e5 f6 6. Qe2 Bf5 7. h3 Qd7 8. g4 Be4
9. Nbd2 O-O-O 10. Nxe4 dxe4 11. Qxe4 fxe5 12. Bg2 Nf6 13. Nxe5 Nxe5 *
Position (FEN): 2kr3r/pppqp1bp/5np1/4n3/3PQ1P1/2P4P/PP3PB1/R1B1K2R w KQ - 0 14
White to move.
Themes: Queenside Attack Middlegame Mate in 1 
Puzzle rating: 620
Best move: Qxb7#