Weakening White's control of f3. Controlling this square will prove critical to White's defence.
17. cxd4 Ne5f3 18. Kg1h1 Ng4h2 19. Bf8xd6
It's time to take the money and run. White now has a significant material advantage of a rook and a pawn.
19... Bc8g4
But Black keeps piling on the pressure.
20. e5
Ne5 was also playable here.
20... Qf6g5
Black's pieces are swarming all over the White king position; I can't fault my opponent for timidity. Note that the lack of Black's dark-squared bishop is critical to White's defence; if Black had preserved it, he could now use it pry open g3.
21. Qd1c1
White maneuvers to trade off some of the attackers, or at least push them onto less threatening squares.
21... Qg5f5 22. Bb3c2 Qf5e6
. . . Qh5 might have been tried here, to maintain pressure on the crucial f3 square.
23. Nc4e3 Nh2xf1
If instead . . . Bh5, then 24.Bf5.
24. Ne3xg4 Qe6xg4
24. . . . (either)Nh2??; 25. Nf6+ and the tables are turned, Black's king is soon mated.
25. Qc1xf1 Nf3d2
One last ditch effort to complicate; after the alternative . . . Nxd4; Qd1 forces more exchanges.
