Chess puzzle (Advantage)
Opening: Sicilian_Defense, Sicilian_Defense_Delayed_Alapin
Moves: 1. e4 c5 2. Nf3 d6 3. c3 Nf6 4. Bb5+ Nc6 5. d4 a6 6. Bd3 cxd4 7. cxd4 Bg4 8.
Be3 Nb4 9. Qa4+ Nc6 10. d5 b5 11. Bxb5 axb5 12. Qxb5 Qa5+ 13. Qxa5 *
Position (FEN): r3kb1r/4pppp/2np1n2/Q2P4/4P1b1/4BN2/PP3PPP/RN2K2R b KQkq - 0 13
Black to move.
Themes:  Opening  
Puzzle rating: 1556
Best move: Nxa5