Chess puzzle (Checkmate)
Moves: 1. b4 e6 2. Bb2 Nf6 3. a3 c5 4. b5 a6 5. a4 axb5 6. axb5 Rxa1 7. Bxa1 d5 8. e3
Be7 9. c4 O-O 10. d3 dxc4 11. dxc4 Qxd1+ 12. Kxd1 Ne4 13. Ke2 Bf6 14. Bxf6 Nxf6
15. f3 Nbd7 16. f4 Nb6 17. Nd2 Rd8 18. Ngf3 Na4 19. e4 Nc3+ 20. Ke3 *
Position (FEN): 2br2k1/1p3ppp/4pn2/1Pp5/2P1PP2/2n1KN2/3N2PP/5B1R b - - 2 20
Black to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 1358
Best move: Ng4#