Chess puzzle (Advantage)
Opening: Sicilian_Defense, Sicilian_Defense_Nyezhmetdinov-Rossolimo_Attack
Moves: 1. e4 c5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 bxc6 5. d4 cxd4 6. Qxd4 e6 7. Bg5 Qa5+ 8.
Nc3 f6 9. Bd2 Ne7 10. O-O Ng6 11. Rae1 Bc5 12. Qd3 Qc7 13. Na4 Be7 14. a3 O-O
15. c4 a5 16. b4 *
Position (FEN): r1b2rk1/2qpb1pp/2p1ppn1/p7/NPP1P3/P2Q1N2/3B1PPP/4RRK1 b - - 0 16
Black to move.
Themes:  Middlegame  
Puzzle rating: 1557
Best move: axb4