Abdel Irada: <<•>Rank and file<•>>In this puzzle position, we find White with active pieces and much pressure against the black kingside. But adding more pressure appears to give time for defense, so we must consider breaking through with a sacrifice.
Fortunately, there's a stock sac right at hand:
<<•>23. Bxh7†!...>
Now, Black *can* decline this offer, but this is another case where I don't propose to examine such lines in depth. It is enough that we have won a pawn and weakened the enemy kingside; converting those advantages is a story for someone else to tell. *I* will assume the sac is accepted.
<<•>23. ...Kxh724. Qh5†, Kg8
25. fxe5...>
With this single pawn capture, White opens a file for one rook (incorporating a deadly threat against f7) and a rank for the other. Now the storm breaks in earnest.
Now comes the defender to the first crossroads: Black has three reasonable options.
<(1) 25. ...Nxe5
26. Bxe5, f6>
Others: (a) 26. ...g6??; 27. Qh8#. (b) 26. ...B/Rxe5?; 27. Qxf7†, Kh7; 28. Rh4†, Qxh4; 29. gxh4
.
<27. Bxf6!, Qc7>
If 27. ...gxf6?!; 28. Qg6†, Kf8 (28. ...Kh8??; 29. Rh4#); 29. Rxf6†, Qxf6; 30. Qxf6†, Kg8; 31. Rg4†, Kh7; 32. Qg7#.
<28. Rh4, gxf6
29. Qh8†, Kf7
30. Qxf6†, Kg8
31. Rh8#>
(Also insufficient is 28. ...Rxe3; 29. Qh8†, Kf7; 30. Qxg7†, Ke8; 31. Rh8†, Bf8; 32. Rxf8#.)
<(2) 25. ...g6
26. Rg4, Nxe5
27. Bxe5...>
Alternatives:
<(2.1) 27. ...Rxe5
28. Rxg6†, Kf8>
On 28. ...fxg6?; 29. Qxg6†, Kh8; 30. Rf7
.
<29. Qh7
>
No defense works: (a) 29. ...f6/f5??; 30. Rg8#. (b) 29. ...Q/Re7??; 30. Rg8#. (c) 29. ...R/Qc7; 30. Rg8†, Ke7; 31. Qxf7#.
<(2.2) 27. ...Bxe5
28. Rxf7!, Kxf7>
Or 28. ...Bg7; 29. Rxg7†, Kxg7; 30. Qxg6†, Kf8; 31. Rf4†, Ke7; 32. Rf7#.
<29. Qxg6†, Kf8>
Or 29. ...Ke7; 30. Qe6†, Kf8; 31. Rg8#.
<30. Qg8†, Ke7
31. Qe6†, Kf8
32. Rg8#>
For the moment, I'm passing over lines in which Black doesn't recapture on e5, since the bishop on b2 then becomes too much of a menace. Provisionally, then, this line also fails.
<(3) 25. ...Be7
26. Qxf7†, Kh8
27. e6
>
The threat is mate on g7, and there is no adequate defense: (a) 27. ...Rg8??; 28. Qh5#. (b) 27. ...Nf6; 28. Rh4†, Nh7; 29. Qxg7#. (c) 27. ...Bf6; 28. Rh4†!, Bxh4; 29. Qxg7#. (d) 27. ...Bf8; 28. Rf5! 1-0.
So far, Black's best chances seem to lie in variation (1), note (b), where he at least escapes mate; however, in all cases the sudden introduction of both of White's rooks with 25. fxe5 creates too many threats to parry.