Chess puzzle (Checkmate)
Moves: 1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Nf6 5. Nf3 Bg4 6. O-O Be7 7. Re1 O-O 8.
Bf4 Nbd7 9. Nbd2 Re8 10. c3 Bd6 11. Bxd6 cxd6 12. Rxe8+ Qxe8 13. Qb3 Nb6 14. a4
Qc6 15. Bb5 Qc7 16. a5 Nbd7 17. h3 Bh5 18. Re1 Qxa5 19. Bxd7 Nxd7 20. Qxb7 Nb6
21. Qxa8+ Nxa8 *
Position (FEN): n5k1/p4ppp/3p4/q2p3b/3P4/2P2N1P/1P1N1PP1/4R1K1 w - - 0 22
White to move.
Themes:  Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 601
Best move: Re8#