Chess puzzle (Advantage)
Opening: Old_Indian_Defense, Old_Indian_Defense_Ukrainian_Variation
Moves: 1. d4 Nf6 2. c4 d6 3. Nc3 e5 4. dxe5 dxe5 5. Qxd8+ Kxd8 6. Bg5 c6 7. Bxf6+ gxf6
8. e4 a5 9. O-O-O+ Kc7 10. g3 Bb4 11. Kc2 Be6 12. a3 Bc5 13. f3 a4 14. f4 f5
15. Bd3 fxe4 16. Nxe4 Bd4 17. Nf3 Nd7 18. Nxd4 exd4 19. Rhf1 Kb6 *
Position (FEN): r6r/1p1n1p1p/1kp1b3/8/p1PpNP2/P2B2P1/1PK4P/3R1R2 w - - 2 20
White to move.
Themes:  Middlegame  
Puzzle rating: 1868
Best move: f5