Maybe simpler is 26.Bh6+ followed by 27.Rg7 ?

Since 26.Bxd6+ Re7 gives black the e8 square to escape giving up the exchange?

One possibility is

25. Bxd6+ Re7 (25... Be7 26. Nxe6+ ) 26.
Nxe6+ Ke8 27. Rg7 Qh5 (diagram below)

click for larger view

28. Rxe7+ Bxe7 29. Ng7+

Hi, <MAJ>. Nice to see you back again... I think :>}

I did indeed mean 23.Nxe6. Toga agreed with the "Not good" part, which I why I deleted the rest of my analysis. I should have made that clear in my post.

<OOPS, I see that See <crafty> and <HelaNubo> have addressed the above, too.>

So correct solution if black would respond kh8 is to give another check to force the king back to g8

22 Bxg6 .. hxg6
23 Rxg6+ .. Kh8
24 Rh6+ (24 Re3?? dxe5 ==)Kg8
25 Re3 and white is picking up the Queen

22 Rxg2 is not as good as Bxg6

As it will lead to a more unclear game.

22 Rxg6 .. hxg6
23 Bxg6 .. dxe5
24 Bxf7 .. kxf7
25 Rxe5

White has Queen and 3 pawns, for a rook and 2 bishops.

click for larger view

I saw almost immediately 22 Bxg6 followed by 23 Rxg6+...

... a glass of Dalwhinnie, 15 year old single malt, with just a drop of water. Boot up the laptop and straight to CG's puzzle of the day.

In a real game, we would worry about the en prise Be5. But this is CG and we laugh in the face of danger and tweak the nipples of fear. Attack, attack!

Of course, 22. Bxg6 hg 23. Rxg6 demands to be played. But I'm in a sadistic move so I home in on 22. Nxe6, with Bxg6 to follow. Now if 22. Qxe6 we can play follow up Bxg6 with Qxg6+ rather than Rxg6+.

Christ, what a difficult Thursday.

<22.?>

White: a2, b2, c3, f2, g2, h2, Nd4, Bd3, Be5, Re1, Rg3, Qc2, Kg1

Black: a6, b5, d6, e6, g6, h7, Nf6, Bb7, Be7, Ra8, Re8, Qf7, Kg8

Material: =

Candidates: <[Bxg6]>

-ML-
Once again, what a difficult Thursday. Quite some variations and some not at very clear. As it is relatively late here I'll not be very generous with variations.

<22.Bxg6!> ripped open, and left for dead. That is what is about to happen Black. Black cannot deny this sacrifice due to Bxf7†, or Bxe8 if the Queen moves, either to f8 or g7.

<22....hxg6 23.Rxg6†> open, now the King has two valuable squares to go to. Kh7 is pointless due to Rxf6† and both the Knight and Queen fall. Qxg6 is even more pointless for just giving away Queen for Rook. So, f8 or h8?

/A\
<23....Kf8> once you see the killer move after Kf8 it is the easiest to analyze.

<24.Bf4!> with dual threats of Bh6† and Nxe6†, due to the Rook being uncovered by the Bishop, Black has to give Queen for piece and be behind a lot. Consider:

/AA\
<24....Qh7 25.Nxe6† Kf7 26.Ng5† > forks are still there, but this one does save White's combination.

/AB\
<24....e5 25.Bh6† Qg7 26.Bxg7† >

/AC\
<24....Ng8 25.Nxe6† Qxe6 26.Rxe6 > and this is also pretty over. Thus it has to be Kh8

/B\
<23....Kh8> now this defense kept me stumped for a LONG time and I doubt it is correct now. Lets see anyways.

<24.Bxf6> strange to take a pinned Knight, but dxe5 is also threatened and White does not want to lose too much material to get the Black Queen in the pocket. Nor Rh6† or Re3 immediately seem to work.

<24....Bxf6 25.Re3> ok. Rook lifting. What defenses does Black have?

<25....Bh4?! (Qh7 26.Rh3 Bh4) 26.Rh3> instead of playing Qh7 immediately, Black now has the option of defending on e7 also. Is not very helpful, though.

/BA\
<26....Qe7 27.Rh6† Kg8 (Kg7 28.Qg6† Kf8 29.Rh8‡ 1-0) 28.R3xh4 > fair enough, White has AT LEAST won the piece back, but Black is going down soon enough.

/BB\
<26....Qh7> IMO the best defense White has to crack.

<27.g3 > but the Bishop is falling, and White wins.

Bleeh. Couldn't get Rh6† to work in the Kh8 variation and it pays. Got the ingame move though, although I forgot to mention it.

/AD\
<24....Bd8 25.Bh6 Ke7 26.Rg7 >

<Maybe Bxf6 does actually win...>

I began by looking at 22. Rxg6 since it seemed the most forcing, but after 22. ... hxg6 23. Bxg6 Qg7 (or Qf8) (23. ... dxe5 24. Bxf7+ Kxf7 25. Rxe5 is also good for Black) 24. Nxe6 Qh6 25. Bxe8 Rxe8 26. Bd4, I concluded that it did not provide enough compensation for White.

I then looked at Bxg6 since it seemed to be the next most forcing move for White. But after 22. Bxg6 hxg6 23. Rxg6+ Kf8 (Kh8 seemed intuitively bad for Black given the pin on f6, so I didn't bother to analyze), I was stuck. But, it was better than Rxg6.

Then, I looked at Nxe6 which seemed promising after Qxe6, when I realized that Black need not take the knight, but instead could play dxe5 which pretty much killed that line of attack. That's when I realized just how valuable the dark squared bishop was for White.

All of White attacking pieces were aligned to light squares which enabled Black's king to escape to a dark square in the event of check. So, I returned to Bxg6 where I realized that Black also had a similar dark square deficiency in that his knight was currently attacking light squares. Only then did the backward bishop move become apparent.

So, now I had 22. Bxg6 hxg6 23. Rxg6+ Kf8 24. Bf4 Bd8 (best, but still bad) 25. Bxd6+ and Black cannot avoid a crushing loss of material. As it turned out, Black resigned before then anyway. Like yesterday's puzzle, the third move was difficult to see, as backward bishop moves are not that intuitive.

One other note is that Black adopts an unusual line to the Sicilian. What is more odd is that Tatai had played this variation as White, and won (!) some years before this game (S Tatai vs J M Bellon Lopez, 1975). He also played this defense again, but without the speculative 3. ... b5 (d5 is the usual move), in the same tournament to better effect (B Ventura vs S Tatai, 1999).

I saw 22.Bxg6,hxg6 23.Rxd6+,Kf8 (23..Kh8 24.Bxf6+,Bxf6 25.Re3 + -) 24.Bf4!,Rc8 (24..Bd8 25.Bxd6+,Be7 26.Nxe6+ + -) 25.Nxe6+,Ke8 26.Rg7!,Qh5 27.Rxe7+,Kxe7 (27..Kd8 28.Rxb7 + -) 28.Ng7+!,Qe5 29.Bxe5

That was my main line, but there are even more options!