Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Berlin_Defense
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. d3 d6 5. h3 Be7 6. O-O Be6 7. Nc3 O-O 8. Bxc6
bxc6 9. Nh2 Nd7 10. f4 exf4 11. Bxf4 Bf6 12. Ng4 Bd4+ 13. Be3 *
Position (FEN): r2q1rk1/p1pn1ppp/2ppb3/8/3bP1N1/2NPB2P/PPP3P1/R2Q1RK1 b - - 4 13
Black to move.
Themes:  Opening  
Puzzle rating: 1373
Best move: Bxg4