Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Exchange_Variation
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. O-O f6 6. d3 Bg4 7. h3 Bh5 8. Be3
Bd6 9. c3 Ne7 10. Nbd2 Qd7 11. Qb3 O-O-O 12. Nc4 *
Position (FEN): 2kr3r/1ppqn1pp/p1pb1p2/4p2b/2N1P3/1QPPBN1P/PP3PP1/R4RK1 b - - 6 12
Black to move.
Themes:  Middlegame  
Puzzle rating: 1246
Best move: Bxf3