Chess puzzle (Checkmate)
Moves: 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8.
Qxf6 Nxf6 9. Nc3 d5 10. exd5 Nb4 11. Bd3 Nfxd5 12. Nxd5 Nxd5 13. c3 O-O 14. O-O
b5 15. Re1 f6 16. Be4 Be6 17. Rd1 Rad8 18. Bxd5 Rxd5 19. Rxd5 Bxd5 20. a4 Bc4
21. axb5 Rd8 22. bxa6 *
Position (FEN): 3r2k1/6pp/P4p2/4p3/2b5/2P5/1P3PPP/R1B3K1 b - - 0 22
Black to move.
Themes:  Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 400
Best move: Rd1#