Chess puzzle (Checkmate)
Moves: 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. f3 Qb6 7. Nb3 g6 8. Bf4
Bg7 9. Qd2 O-O 10. O-O-O a5 11. Na4 Qc6 12. Nc3 a4 13. Bb5 axb3 14. Bxc6 bxa2
15. Nxa2 Nxc6 16. Kb1 Be6 17. b3 Nd7 18. Bh6 Bf6 19. g4 Rxa2 20. Kxa2 Ra8+ 21.
Kb1 *
Position (FEN): r5k1/1p1npp1p/2npbbpB/8/4P1P1/1P3P2/2PQ3P/1K1R3R b - - 2 21
Black to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 760
Best move: Ra1#