Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Morphy_Defense
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. d4 b5 6. Bb3 exd4 7. Nxd4 Bb7 8. Nc3
Nf6 9. Bg5 Be7 10. O-O O-O 11. f4 *
Position (FEN): r2q1rk1/1bp1bppp/p1np1n2/1p4B1/3NPP2/1BN5/PPP3PP/R2Q1RK1 b - - 0 11
Black to move.
Themes:  Opening  
Puzzle rating: 1839
Best move: Nxd4