Chess puzzle (Advantage)
Opening: Modern_Defense, Modern_Defense_Two_Knights_Variation
Moves: 1. e4 g6 2. Nf3 Bg7 3. d4 d6 4. Nc3 e6 5. Bg5 f6 6. Be3 Nh6 7. h3 Nf7 8. d5 e5
9. Bb5+ Bd7 10. Bxd7+ Qxd7 11. Qd2 O-O 12. h4 h6 13. O-O-O a6 14. Rhg1 b5 15.
a3 a5 16. Ne2 Na6 17. b3 c5 18. g4 c4 19. g5 h5 *
Position (FEN): r4rk1/3q1nb1/n2p1pp1/pp1Pp1Pp/2p1P2P/PP2BN2/2PQNP2/2KR2R1 w - - 0 20
White to move.
Themes:  Middlegame  
Puzzle rating: 1218
Best move: gxf6