Chess puzzle (Advantage)
Opening: Queens_Gambit_Accepted, Queens_Gambit_Accepted_Old_Variation
Moves: 1. d4 d5 2. c4 dxc4 3. e3 Nc6 4. Bxc4 e5 5. Nc3 exd4 6. exd4 Qxd4 7. Qxd4 Nxd4
8. Bd3 Bb4 9. Bd2 Nf6 10. O-O-O O-O 11. a3 Nb3+ 12. Kc2 Nxd2 *
Position (FEN): r1b2rk1/ppp2ppp/5n2/8/1b6/P1NB4/1PKn1PPP/3R2NR w - - 0 13
White to move.
Themes: Hanging Piece Middlegame  
Puzzle rating: 1750
Best move: axb4