Chess puzzle (Checkmate)
Opening: Queens_Pawn_Game, Queens_Pawn_Game_Chigorin_Variation
Moves: 1. Nc3 d5 2. d4 Nc6 3. Bf4 Bf5 4. Nf3 Be4 5. Nxe4 dxe4 6. Nd2 Nxd4 7. Nxe4 Qd5
8. Nc3 Qf5 9. Qxd4 Rd8 10. Qxa7 Qxf4 11. Qxb7 *
Position (FEN): 3rkbnr/1Qp1pppp/8/8/5q2/2N5/PPP1PPPP/R3KB1R b KQk - 0 11
Black to move.
Themes:  Middlegame Mate in 1 
Puzzle rating: 900
Best move: Qd2#