Chess puzzle (Advantage)
Opening: Modern_Defense, Modern_Defense_Other_variations
Moves: 1. e4 g6 2. Nf3 e6 3. d4 h6 4. Bc4 Bg7 5. Nc3 a6 6. Be3 b5 7. Bb3 Nc6 8. a3 b4
9. Ne2 bxa3 10. bxa3 Bb7 11. O-O Na5 12. d5 Bxa1 *
Position (FEN): r2qk1nr/1bpp1p2/p3p1pp/n2P4/4P3/PB2BN2/2P1NPPP/b2Q1RK1 w kq - 0 13
White to move.
Themes:  Middlegame  
Puzzle rating: 702
Best move: Qxa1