Chess puzzle (Advantage)
Opening: Nimzowitsch_Defense, Nimzowitsch_Defense_Franco-Nimzowitsch_Variation
Moves: 1. e4 Nc6 2. Nf3 e6 3. Bc4 d5 4. exd5 exd5 5. Bb5 Bd7 6. O-O Nge7 7. c3 g6 8.
Ng5 Bh6 9. d3 O-O 10. Re1 Nf5 11. Nf3 Bxc1 12. Qxc1 Nce7 13. c4 Bxb5 14. cxb5
Qd7 15. Nc3 c6 16. Ne5 Qd6 17. bxc6 bxc6 18. Qg5 *
Position (FEN): r4rk1/p3np1p/2pq2p1/3pNnQ1/8/2NP4/PP3PPP/R3R1K1 b - - 1 18
Black to move.
Themes:  Middlegame  
Puzzle rating: 1400
Best move: f6