Chess puzzle (Advantage)
Opening: Queens_Gambit_Declined, Queens_Gambit_Declined_Marshall_Defense
Moves: 1. d4 Nf6 2. c4 d5 3. cxd5 Nxd5 4. e4 Nf6 5. e5 Nd5 6. Bc4 c6 7. Bxd5 cxd5 8.
Nf3 Bg4 9. O-O Nc6 10. Nc3 e6 11. Bg5 *
Position (FEN): r2qkb1r/pp3ppp/2n1p3/3pP1B1/3P2b1/2N2N2/PP3PPP/R2Q1RK1 b kq - 1 11
Black to move.
Themes:  Middlegame  
Puzzle rating: 1354
Best move: Bxf3