Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Steinitz_Defense
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 d6 4. d3 Bd7 5. Bg5 Nf6 6. O-O Be7 7. Nc3 a6 8. d4 *
Position (FEN): r2qk2r/1ppbbppp/p1np1n2/1B2p1B1/3PP3/2N2N2/PPP2PPP/R2Q1RK1 b kq - 0 8
Black to move.
Themes:  Opening  
Puzzle rating: 1613
Best move: axb5