Chess puzzle (Advantage)
Opening: Queens_Pawn_Game, Queens_Pawn_Game_Chigorin_Variation
Moves: 1. d4 d5 2. Nc3 Nf6 3. e3 Nc6 4. Nge2 Bg4 5. f3 Bf5 6. Bd2 e6 7. g3 h6 8. Bg2
Bb4 9. O-O Qd7 10. Nf4 O-O-O 11. Nce2 Bxd2 12. Qxd2 e5 13. Nc3 *
Position (FEN): 2kr3r/pppq1pp1/2n2n1p/3ppb2/3P1N2/2N1PPP1/PPPQ2BP/R4RK1 b - - 1 13
Black to move.
Themes:  Middlegame  
Puzzle rating: 1304
Best move: exf4