Chess puzzle (Checkmate)
Moves: 1. d4 Nf6 2. Bf4 d6 3. Nc3 g6 4. e4 Bg7 5. Qd2 Nc6 6. O-O-O O-O 7. Bh6 a5 8. h4
a4 9. a3 Bxh6 10. Qxh6 Ng4 11. Qf4 Qe8 12. h5 e5 13. dxe5 Qxe5 14. Qd2 b5 15.
f3 Nf6 16. hxg6 fxg6 17. Bxb5 Bd7 18. Bxa4 Qc5 19. Bb3+ Kg7 20. Nd5 Rxa3 21.
Nxf6 *
Position (FEN): 5r2/2pb2kp/2np1Np1/2q5/4P3/rB3P2/1PPQ2P1/2KR2NR b - - 0 21
Black to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 866
Best move: Ra1#