Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. d4 exd4 3. Nf3 Bb4+ 4. Bd2 Bc5 5. Bg5 f6 6. Bf4 Nc6 7. a3 Nge7 8.
b4 Bb6 9. b5 Na5 10. Nxd4 d5 11. Nb3 Nxb3 12. cxb3 Ng6 13. Bg3 Be6 14. exd5
Bxd5 15. f3 Qe7+ 16. Be2 O-O-O 17. Qc2 Rhe8 18. Nc3 Qe3 19. Na4 Bxb3 20. Nxb6+
axb6 *
Position (FEN): 2krr3/1pp3pp/1p3pn1/1P6/8/Pb2qPB1/2Q1B1PP/R3K2R w KQ - 0 21
White to move.
Themes: Queenside Attack Middlegame Mate in 1 
Puzzle rating: 1451
Best move: Qxc7#