Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Berlin_Defense
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Bd6 5. Re1 Nd4 *
Position (FEN): r1bqk2r/pppp1ppp/3b1n2/1B2p3/3nP3/5N2/PPPP1PPP/RNBQR1K1 w kq - 8 6
White to move.
Themes:  Opening  
Puzzle rating: 851
Best move: Nxd4