Chess puzzle (Checkmate)
Moves: 1. d4 d5 2. Bf4 Nf6 3. Nf3 e6 4. e3 c5 5. c3 Bd6 6. Bg3 O-O 7. Nbd2 Nc6 8. Bxd6
Qxd6 9. dxc5 Qxc5 10. Nb3 Qb6 11. Nfd4 Nxd4 12. exd4 Bd7 13. Bd3 Bb5 14. O-O
Bxd3 15. Qxd3 a5 16. Qc2 Ne4 17. f3 a4 18. fxe4 axb3 19. axb3 dxe4 20. Qxe4
Qxb3 21. Rxa8 Rxa8 22. Qf3 Rf8 23. Qe2 Ra8 24. Kh1 Ra2 25. Rb1 Qxc3 26. bxc3
Rxe2 27. Rxb7 *
Position (FEN): 6k1/1R3ppp/4p3/8/3P4/2P5/4r1PP/7K b - - 0 27
Black to move.
Themes:  Endgame, Rook Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 608
Best move: Re1#