Abdel Irada: <<•> Master of Misdirection? <•>>Whenever White played Qe1, I suspect that it was a dual-purpose maneuver: It overdefends the pawn on c3 and prepares a kingside attack. Black apparently either missed, underestimated or simply couldn't find a defense to the threat, and hence our puzzle.
On Monday, I discussed a kind of queen sacrifice: a mating combination begun by giving up Her Majesty on h7 and ended with a mate delivered by the rook on h8 (which is defended by a bishop on f6).
So frequently does this pattern appear that it is sometimes called a "stock" sacrifice.
In the same post, I referred to another type of stock sacrifice, and very obligingly <chessgames.com> has supplied us with a puzzle using it. The kind of attack you see here, beginning with the characteristic Bxh7†, is, I am certain, the most common of them all, so I will add a descriptive supplemental title:
<<•> Stock Bishop Sac #1 <•>>
When I tell you that in some kinds of positions, giving up a bishop on h7/h2 should be almost reflexive, I necessarily invite another and more awkward question: *What* kinds of positions?
Without professing anything resembling a thorough answer, I note several criteria:
•The h-pawn is defended only by the king.
•The attacker's queen is in a position to come to the h-file in one move (or two if the intervening move gains time, as by giving check).
•(Usually) the attacker has a knight on f3 or e4, in position to move to g5.
•There are few defenders on the kingside. (This is necessarily nebulous.)
•No defender is in position to stop a threat with gain of time (as by a knight moving to f6, defending h7 and attacking a queen on h5).
(Sometimes) the attacker controls the f- or e-file, cutting off the king's retreat.
•(Often) the defender's queen's bishop is either missing or locked away from the kingside.
Here we find all but one of these conditions in place, so all systems are go.
<<•> 24. Bxh7† ... >
Again: stock sac, so no exclam. Sometimes the attack is difficult, but here White has such a preponderance that there is no reason to hesitate.
Black *can* decline but shouldn't: (a) 24. ...Kh8 25. Qh4 
. White has won a pawn and ruined Black's kingside for nothing, and the mate threats following 26. Bg6† are unstoppable.
<<•> 24. ...Kxh725. Ng5† ... >
Now there are four moves:
< (1) 25. ...Kh8?
26. Qh4†, Bh5
27. Qxh5†, Kg8
28. Qh7# >
< (2) 25. ...Kg8
26. Qh4, Bg6
27. Rh3 >
Thanks to the white rook on the open f-file (abetted by the pawn on e6), there is no escape.
< (3) 25. ...Kh6
26. Qh4†, Bh5 >
Ineffective is (b) 26. ...Kg6 27. Qh7†!, Kxg5 28. Rg3#.
< 27. Nf7† >
White mates in three.
< (4) 25. ...Kg6
26. Qg3 >
The threat is 27. Ne4†, winning the queen, and Black has no good reply.
Of no use, for example, are
(c) 27. ...Qb6 28. Nf7†, when White mates as in line (3) above;
(d) 27. ...Kh6 28. Qh4†, and White again wins as in line (3); or
(e) 27. ...Kh5 28. Qh3†, Kxg5 (28. ...Kg6 29. Qh7† as in (3) above) 29. Rg3#.
For all of Black's apparent busy activity on the queenside, his position on the kingside has been sown with poisoned seeds and death is written upon his face.
Review the list above, note that Black satisfied six of the seven criteria to trigger the "automatic" stock bishop sac on h7, and then observe some more: What *other* special characteristics in this position might contribute to the strength of White's attack?
∞
Kibitzing
sac: 24.Bxh7+
