Chess puzzle (Checkmate)
Opening: Queens_Gambit_Accepted, Queens_Gambit_Accepted_Showalter_Variation
Moves: 1. d4 Nf6 2. Nf3 d5 3. c4 dxc4 4. Nc3 Bg4 5. e4 e6 6. Qa4+ c6 7. Qxc4 Nbd7 8.
Be2 Nb6 9. Qd3 Bb4 10. Bg5 h6 11. Bh4 g5 12. Bg3 Qe7 13. a3 Bxc3+ 14. bxc3
O-O-O 15. O-O Nh5 16. a4 a6 17. Rab1 Nd7 18. Qxa6 bxa6 *
Position (FEN): 2kr3r/3nqp2/p1p1p2p/6pn/P2PP1b1/2P2NB1/4BPPP/1R3RK1 w - - 0 19
White to move.
Themes: Queenside Attack Middlegame Mate in 1 
Puzzle rating: 1464
Best move: Bxa6#