Chess puzzle (Checkmate)
Moves: 1. Nf3 e6 2. d4 d5 3. c4 Nf6 4. b3 h6 5. Nc3 Bb4 6. Bd2 dxc4 7. bxc4 Nc6 8. e3
O-O 9. Bd3 a5 10. O-O Nh7 11. Qc2 f5 12. a3 Be7 13. Rfe1 b6 14. a4 Bf6 15. Rab1
Rb8 16. Nb5 Ba6 17. Bc3 g6 18. e4 Bxb5 19. cxb5 Nxd4 20. Nxd4 Bxd4 21. Bxd4
Qxd4 22. exf5 gxf5 23. Rxe6 Rbe8 24. Rxe8 Rxe8 25. Bxf5 Nf6 26. Rd1 Kg7 27.
Rxd4 *
Position (FEN): 4r3/2p3k1/1p3n1p/pP3B2/P2R4/8/2Q2PPP/6K1 b - - 0 27
Black to move.
Themes:  Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 647
Best move: Re1#