Chess puzzle (Advantage)
Opening: Russian_Game, Russian_Game_Cozio_Attack
Moves: 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. Qe2 Qe7 6. Nc3 Nxc3 7. dxc3 Bg4
8. Qxe7+ Bxe7 9. Be2 Nc6 10. O-O O-O-O 11. Re1 h6 12. Nd4 Bd7 13. Nxc6 bxc6 *
Position (FEN): 2kr3r/p1pbbpp1/2pp3p/8/8/2P5/PPP1BPPP/R1B1R1K1 w - - 0 14
White to move.
Themes:  Middlegame  
Puzzle rating: 521
Best move: Ba6+