Chess puzzle (Checkmate)
Opening: French_Defense, French_Defense_Advance_Variation
Moves: 1. e4 e6 2. d4 d5 3. e5 c5 4. c3 a6 5. Nf3 b5 6. b3 Bb7 7. Bd3 c4 8. bxc4 dxc4
9. Bc2 Ne7 10. O-O Nd5 11. Ng5 Be7 12. Qg4 h5 13. Qg3 h4 14. Qg4 Bc8 15. Be4
Nc6 16. h3 Bd7 17. Re1 f5 18. exf6 Nxf6 19. Nxe6 Nxg4 *
Position (FEN): r2qk2r/3bb1p1/p1n1N3/1p6/2pPB1np/2P4P/P4PP1/RNB1R1K1 w kq - 0 20
White to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 1383
Best move: Bg6#