Chess puzzle (Checkmate)
Moves: 1. e4 e5 2. Bc4 Nf6 3. d4 exd4 4. Nf3 d5 5. exd5 Nxd5 6. O-O Nc6 7. Re1+ Be6 8.
Ng5 Qd7 9. Bxd5 Qxd5 10. Nc3 Qd7 11. Nce4 Be7 12. Nxe6 Qxe6 13. Ng5 Qg6 14.
Rxe7+ Nxe7 15. Qe2 O-O-O 16. Bf4 Nd5 17. Bd2 Rhe8 18. Qc4 Nb6 19. Qxf7 Qxc2 20.
Rc1 Qxc1+ 21. Bxc1 *
Position (FEN): 2krr3/ppp2Qpp/1n6/6N1/3p4/8/PP3PPP/2B3K1 b - - 0 21
Black to move.
Themes:  Endgame Back Rank Mate, Mate in 1 
Puzzle rating: 473
Best move: Re1#