Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. Nf3 d6 3. Bc4 Bg4 4. d3 Nd7 5. Nbd2 g6 6. h3 Be6 7. Bxe6 fxe6 8.
Nc4 Bg7 9. Bg5 Ngf6 10. h4 h6 11. Bd2 Qe7 12. b4 Nh5 13. Na5 O-O-O 14. c4 Ndf6
15. Qa4 Qd7 16. b5 Nf4 17. Nc6 a6 18. Rb1 Nxd3+ 19. Ke2 Nc5 20. bxa6 Nxa4 *
Position (FEN): 2kr3r/1ppq2b1/P1Nppnpp/4p3/n1P1P2P/5N2/P2BKPP1/1R5R w - - 0 21
White to move.
Themes: Advanced Pawn, Queenside Attack Middlegame Mate in 1 
Puzzle rating: 1495
Best move: axb7#