Makes you wonder how that black rook got to b3. Shouldn't it have been the queen's rook? The game will be interesting.

With a large number of black's pieces stuck on the queen side (both rooks, a bishop and a knight), it seems that an assault on the king is in order for white.

Let's try to pick out some candidate moves. There's

- 30 Nxh6+
- 30 Nf6+
- 30 Rxe6
- 30 Bf6

I think it's a combination of these moves, and that the order is important. First let's go for

30 Rxe6 Nxe6

Or else black just loses a pawn and has a lousy position to show for it.

31 Qg6

This has a couple of threats, namely 32 Nf6+ (picking up the queen) and 32 Rxe6. Even 32 Nxh6+ and if 32...Kh6 then 33 Nf7+ and 34 Ng5 looks promising.

What can black play? Not 31...Ne7 because 32 Nf6+ Kf8 (32...Kh8? 33 Qh7#) 33 Nxd7+. And not 31...Qf7 32 Nxh6+ and 33 Nxf7. The only move that saves the knight appears to be

31...Nf8

But this allows

32 Nf6+ Kh8 33 Re8

threatening both 34 Rxf8# and 34 Qh7#. Black must give up the queen with

33...Qxe8 34 Qxe8

and after

34...gxf6 35 Qxf8+ Kh7 36 Qf7+ Kh8 37 Bxf6#

is mate.

I'm sure there are a lot of lines I'm not looking at, but it's 1:30a, and I'm done for this evening.

Time to check.

Material: B for N. White has a battery Re1 and Re2 on the e-file against Pe6. His Qc2 is active, attacking the light squares near the Black Kg8; Ng4 and Bh4 attack the dark squares. The Black Pg7 must protect against the move Nf6, forking Qd7 and Kg8, so Bh4 may occupy f6 with impunity. The Black Nf8 must protect the light squares around Kg8, to prevent the moves Qg6 and then Nf6+. Only the White Bf1 needs to be activated.

Candidates (30.): Rxe6 (deflecting Nf8)

30.Rxe6 Nxe6 [else, drop a P and permit invasion by the Rs]

Candidates (31.): Qg6, Rxe6

31.Qg6 (threatening 32.Nf6+ then 33.Nxd7+ or 33.Qh7#)

To meet the threats, Black must move Kg8, because moves with Ne6 or Qd7 are ineffective.

(1) 31…Nf8 32.Re8 Qxe8 33.Nxh6+ Kh8 34.Qxe8 (threatening 35.Qxf8+)

34…Nb6 [gxh6 35.Qxf8+ Kh7 36.Qf7+ Kh8 37.Bxf6#] 35.Bd8 Kh7 36.Qxf8

36…Kxh6 [gxh6 Qf7+ and mate soon] 37.Qxd6+ K moves 38.Bxb6

leaving White with Q+B+3Ps for 2Rs.

(2) 31…Qf7 32.Nh6+ winning Qf7.

(3) 31…Q other feasible move 32.Rxe6,

threatening 33.Re8# and if Nc8 moves, 33.Re7 and mate soon, so there is no feasible defense.

The Kg8 has 2 legal moves.

(4) 31…Kh8 32.Rxe6

threatening 33.Re8#, 33.Nf6 gxf6 [else, 34.Qh7#] 34.Bxf6+ Qg7 35.Qxg7#, and 33.Re7

There is no feasible defense.

(5) 31…Kf8 32.Nxh6 (threatening 33.Qh7 34.Qh8#)

Black cannot accept the sacrifice, which takes the critical defensive square f7 away from Qd7:

32…gxh6 33.Rxe6 (threatening 34.Rf6+ and mate soon)

33…Ra7 34.Rf6+ Qf7 35.Rxf7+ Rxf7 36.Qxh6+

White emerges with Q+2Ps and the initiative against an open K for 2Rs, so Black must refuse the sacrifice. To prevent the threat in 32.Nxh6, Black cannot prevent 33.Qh7 with 32…Ng5 33.Bxg5, so he must prepare to play 33…gxh6.

32…Ra7 [or Nb6] 33.Rxe6 (threatening 34.Qf4+)

Because 33…gxh6 is a transposition of a previous losing line, and because of 33…Ne7 34.Qf7#, Black can resign.

Funny how some of these sacrifice games go-the sacker often winds up AHEAD in material-Doesn't that make it an investment rather than a sacrifice? JW

It might have been, had White played 27.Ng4! with a big advantage (27...Nxg4 28.Qg6!). But since White played inaccurately with both 27.Bh4 and 28.Ng4, Black could have held with 29...Qe8, (over-)protecting g6; so I think 29...Qd7? should be considered as Black's decisive mistake.

I thought he would play 18 ... Ne4 which simplifies.

Any help on this is appreciated, since the puzzles are way over my head anyway!

Dynamic Evaluation: Knight moving to f6+ would necessitate g7 taking f6 or losing the Queen. That exposes the black King but how to take advantage of that? Taking f6 with the Bishop helps but doesn't allow the white Queen to engage because of knight on f8. Solution,attack e6 with Rooks to deflect Nf8.

Dynamic Assessment: Reasonable moves, Rxe6, Ng4-f6,

30.Rxe6 ...Nxe6 31.Ng4-f6+ ...gxf6 32.Qg6+ ...Kh8

33.Bxf6#

PM=

I knew from the looks of the position that the Rook and the Knight would probably be sac'd. I also wanted to take advantage of the Royal Fork with the Knight. I was thinking something like:

30. Rxe6 Nxe6
31. Nf6 gx6 (by necessity, to save the Queen)

32...Kh8 33. Bxf6# (too easy)

<or to prevent mate>

32. Qg6+ Kf8 33. Qxh8+

At this point Black has only a few moves to choose from and cannot escape to the Queenside because of the dark squared bishop on h4. I could see 3 possibilities.

33...Kf7 34. Qxf7+ followed by ?

33...Ke8 34. Rxe6+ Ne7 35. Rxe7+ Qxe7 36 Qxe7#

33...Kg8 34. Rxe6 followed by ?

This is about as far as I can go without making the moves on a board.

click for larger view

(16-ply) Rybka 2.3.2a
1. (1.91): 28...Bb7 29.Bh7+ Kh8 30.Nf5 Nf8 31.Nxg7 Qd7 32.Nxe6 Qxh7 33.Nxf8 Qxc2 34.Rxc2 Kg8 35.Ne6 Rb8 36.Nd8 Ba8 37.Bf6 Nb6 38.f4 Rd3 39.f5 Nd7 40.Re8+ Nf8

2. (2.03): 28...Rxd3 29.Rxd3 Ra7 30.Rd2 Nf8 31.Red1 Rd7 32.Bg3 Bb7 33.h3 Nh7 34.Qg6 Nf8 35.Qg4 Qb6 36.Be5