Chess puzzle (Advantage)
Opening: Ruy_Lopez, Ruy_Lopez_Berlin_Defense
Moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Bc5 5. Nxe5 Nxe5 6. d4 Bxd4 7. Qxd4 Nc6
8. Bxc6 bxc6 9. Bg5 d6 10. Nc3 O-O 11. f4 c5 12. Qd3 Bb7 13. Rad1 Re8 14. e5
dxe5 15. Qxd8 Raxd8 16. Rxd8 Rxd8 17. fxe5 Re8 *
Position (FEN): 4r1k1/pbp2ppp/5n2/2p1P1B1/8/2N5/PPP3PP/5RK1 w - - 1 18
White to move.
Themes:  Endgame  
Puzzle rating: 1129
Best move: exf6