Chess puzzle (Checkmate)
Moves: 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 c6 5. Bg5 h6 6. Bxf6 Qxf6 7. e3 Nd7 8. cxd5
exd5 9. Bd3 Bb4 10. Qc2 O-O 11. O-O-O b5 12. Bh7+ Kh8 13. Bd3 a5 14. a3 Bxc3
15. Qxc3 b4 16. axb4 axb4 17. Qxb4 Rb8 18. Qa3 c5 19. dxc5 Nxc5 20. Qxc5 *
Position (FEN): 1rb2r1k/5pp1/5q1p/2Qp4/8/3BPN2/1P3PPP/2KR3R b - - 0 20
Black to move.
Themes: Queenside Attack Middlegame Mate in 1 
Puzzle rating: 722
Best move: Qxb2#