Chess puzzle (Crushing)
Opening: Queens_Pawn_Game, Queens_Pawn_Game_Chigorin_Variation
Moves: 1. Nf3 Nc6 2. d4 d5 3. g3 Nf6 4. Bg2 e6 5. O-O h6 6. c4 dxc4 7. Nc3 Bb4 8. a3
Bxc3 9. bxc3 O-O 10. Qa4 Nd5 11. Qxc4 Na5 12. Qb4 *
Position (FEN): r1bq1rk1/ppp2pp1/4p2p/n2n4/1Q1P4/P1P2NP1/4PPBP/R1B2RK1 b - - 2 12
Black to move.
Themes:  Middlegame  
Puzzle rating: 1050
Best move: Nxb4