Chess puzzle (Checkmate)
Moves: 1. d4 Nf6 2. Nc3 g6 3. Bg5 Bg7 4. e4 d6 5. Nf3 Nbd7 6. Bc4 O-O 7. O-O b6 8. Qe2
e5 9. dxe5 Nxe5 10. Bd5 Nxf3+ 11. Qxf3 Rb8 12. Bb3 Bb7 13. Bd5 Ba6 14. Rfe1 Re8
15. Bc6 Re5 16. Bh4 Rh5 17. Bg3 Bb7 18. e5 Bxc6 19. Qxc6 dxe5 20. Bxe5 Rc8 21.
Nb5 Ng4 22. Bxc7 Qd2 23. Qf3 Rxb5 24. Re7 Rf5 25. Qxg4 Qxf2+ 26. Kh1 Qf1+ 27.
Rxf1 *
Position (FEN): 2r3k1/p1B1Rpbp/1p4p1/5r2/6Q1/8/PPP3PP/5R1K b - - 0 27
Black to move.
Themes:  Middlegame Back Rank Mate, Mate in 1 
Puzzle rating: 694
Best move: Rxf1#