Chess puzzle (Checkmate)
Moves: 1. e4 c5 2. d4 cxd4 3. Nf3 Nc6 4. Nxd4 e5 5. Nb3 Bb4+ 6. Bd2 Bxd2+ 7. Qxd2 a5
8. Bb5 a4 9. Nc5 Nf6 10. Nc3 O-O 11. Bxa4 Qb6 12. Nb3 Nxe4 13. Nxe4 Rxa4 14.
Nec5 Rc4 15. Nxd7 Bxd7 16. Qxd7 Rd8 17. Qh3 Re4+ 18. Kf1 Nd4 19. Nxd4 Qxd4 20.
Qb3 Qd1+ 21. Rxd1 *
Position (FEN): 3r2k1/1p3ppp/8/4p3/4r3/1Q6/PPP2PPP/3R1K1R b - - 0 21
Black to move.
Themes:  Endgame, Queen and Rook Endgame Mate in 1 
Puzzle rating: 821
Best move: Rxd1#