Chess puzzle (Advantage)
Opening: Zukertort_Opening, Zukertort_Opening_Slav_Invitation
Moves: 1. Nf3 c6 2. g3 d5 3. Bg2 Bg4 4. d3 Bxf3 5. Bxf3 e6 6. c4 Nf6 7. Qb3 Qb6 8. Be3
Bb4+ 9. Nc3 Bxc3+ 10. bxc3 Qc7 11. cxd5 Nxd5 12. Bxd5 cxd5 13. Qb4 Nc6 14. Qa3
b6 15. Rb1 Kd7 16. Bf4 Qb7 17. O-O Rhc8 18. d4 Na5 *
Position (FEN): r1r5/pq1k1ppp/1p2p3/n2p4/3P1B2/Q1P3P1/P3PP1P/1R3RK1 w - - 1 19
White to move.
Themes:  Middlegame  
Puzzle rating: 1869
Best move: Qxa5