Chess puzzle (Advantage)
Opening: Sicilian_Defense, Sicilian_Defense_Scheveningen_Variation
Moves: 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be2 e6 7. Be3 b5 8. a3
Bb7 9. f3 Be7 10. Qd2 Nc6 11. O-O-O Rc8 12. g4 Nd7 13. Bxb5 *
Position (FEN): 2rqk2r/1b1nbppp/p1npp3/1B6/3NP1P1/P1N1BP2/1PPQ3P/2KR3R b k - 0 13
Black to move.
Themes:  Middlegame  
Puzzle rating: 1040
Best move: axb5