Chess puzzle (Checkmate)
Moves: 1. d4 e6 2. Nf3 d5 3. e3 c5 4. Bb5+ Bd7 5. Qd3 c4 6. Bxd7+ Qxd7 7. Qd1 Nc6 8.
Ne5 Nxe5 9. dxe5 Bb4+ 10. c3 Ba5 11. b4 Bb6 12. a4 a5 13. b5 Ne7 14. Ba3 O-O
15. f4 Rfe8 16. Qf3 Nf5 17. Bc1 Qe7 18. O-O f6 19. Na3 fxe5 20. fxe5 Rf8 21.
Qh3 Nh6 22. Nc2 Rxf1+ 23. Kxf1 Rf8+ 24. Kg1 Qf7 25. Ba3 Qf2+ 26. Kh1 Qf1+ 27.
Rxf1 *
Position (FEN): 5rk1/1p4pp/1b2p2n/pP1pP3/P1p5/B1P1P2Q/2N3PP/5R1K b - - 0 27
Black to move.
Themes:  Middlegame Back Rank Mate, Mate in 1 
Puzzle rating: 500
Best move: Rxf1#