Chess puzzle (Advantage)
Opening: Four_Knights_Game, Four_Knights_Game_Italian_Variation
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. Nc3 Nf6 5. O-O a6 6. d4 exd4 7. Nxd4 *
Position (FEN): r1bqk2r/1ppp1ppp/p1n2n2/2b5/2BNP3/2N5/PPP2PPP/R1BQ1RK1 b kq - 0 7
Black to move.
Themes:  Opening  
Puzzle rating: 1681
Best move: Bxd4