2025/05/31 DPA: "Take It Or Leave It"

White to move:

.

Black has dark square weaknesses.

The Bishop and Knight cannot deliver check but they can control squares.

1. Qh8+ Kxh8 and if White could safely land Rc8, that would lead to checkmate.

But c8 is protected twice.

White can remove one defender with 1. Bxb6.

White does have 2. Rc7 and if 2. ... Qxd5  3. Rc8+.

But 2. ... Qe8 protects the back rank.

If White could attract the Black King to f8, then Qh8 would be checkmate.

White does not want the Black Rook to move because it's blocking the key f7 escape.

White does NOT have 2. Rc7 due to the Black Bishop on h2 [RBBS].

White also does not want Black to move his h pawn as that makes room on h7 for the King [another light square].

1. Bxb6 axb6  2. Qxb6 is too slow and it hits the wrong square d8; White wants to hit c8 to support the Rook.

What about 2. Qb5, to attack the Queen?  If 2. ... Qxb5  3. Rc8+ Rf8  4. Rxf8#.

Every other Queen move either loses the Queen or cedes control of c8.

Best appears to be to avoid recapturing and play a defensive move to allow the King to get to a light square or maybe 2. ... a6, which prevents 3. Qb5.

Why not play Qb5 immediately?  There's no compulsion to move since the Black Queen is protected by the Knight so Black could play ... Rf6 or ... h5 for light square access.

Oh, even more important is that Black can now capture since the Black Knight defends c8 so 2. Rc8+ fails.

Remember:  neither the Bishop nor the Knight can check so White cannot sac both Rook and Queen.

1. Qb5 Qxb5  2. Bxb6 Qb4+  3. Kd1 h5  4. Rc8+ Kh7  5. Ng5+ Kg7  6. Bd4+ Rf6

So 1. Qb5 is out.

But 1. Bxb6 only wins a piece and Black is currently up 3 pawns so material is even.  That's no Saturday solution.

Are there any chances on the Kside?  How can we shift material over there?

1. f4 to open the 2nd rank for the Queen to slide over doesn't seem like it accomplishes much:  Black's h pawn is defended by the Rook.

Same for 1. Ke2 to make room for the Rook.

I don't see any Rook move that's useful.

1. d6?  No.

Any Bishop move?  d2 does nothing.  Advancing to f4, g5, or h6 does nothing except add an attacker to g7.  d4 or c5 does nothing.

I doubt it's a King move.  No castling possible.

A Queen move?  A setup move?

Note that Black has no checks but the d pawn is en prise and if Black's Queen can capture it, she then threatens the Knight, which I think is a key attacker of the dark squares.

So if White does make a setup move, it might involve protecting the d pawn while threatening something else.

But does White have time to allow Black to play ... Rf7 or ... h5?  It wouldn't appear so.

I found something:  1. Bxb6 a6  2. Bc7, threatening to win another piece, which would be winning.  If 2. ... Bxc7  3. Rxc7 Qe8  4. Qc3, threatening 5. Rc8, pinning the Queen at a minimum.

There's no way Black can protect the Bishop although it could move to g1 but 3. Be5 again threatens 4. Rc7.

Wait:  what about 1. Bxb6 a6  2. Qc3, threatening 3. Qc8+ Qxc8  4. Rxc8+ Rf8  5. Rxf8#.

The Black Rook can't move up the f file because that allows 3. Qg7#.

Ah, but 2. ... h6/h5 gives an escape.

What am I missing?

What weak points am I not exploiting?

Do I have the right idea but the wrong order [the Bxb6 and Qb5 combo comes to mind]?

What about 1. Qc3 again?  This threatens 2. Bxb6 then 3. Qc8+.

But that's 2 moves for Black to counter.

What about simply 1. ... h6 to gain luft?

2. Bxb6 axb6  3. Qc8+ Qxc8  4. Rxc8+ Kh7.

Once Black can play ... h6, a subsequent Ng5 is not possible.

Bxb6 and Qc3 are interchangeable so neither can be the solution.

1. Bh6 stops the h pawn from moving but gives Black time for a counter like 1. ... Qxd5 but 2. Qxb6 axb6  3. Rc8+ leads to checkmate.

But Black can play 2. ... Qd7

• 1. Qb5 does not win due to the perpetual
• 1. Bxb6 does not win due to ... h6 [this wins a piece but White is down 3 pawns]
• 1. Qc3 allows 1. ... h6
• The Knight must stay put

This leaves 1. Bh6 and it freezes the h pawn, preserving the mating net.  But 1. ... Nxd5  2. Qb5 Nb6!  3. Qxd7 Nxd7  4. Rc8 Nf8 and White only wins a piece and in this variation, he's also lost a pawn so now he's down 4 pawns!

Can the King escape perpetual?  No, because Black can play ... Rxf2+ at an opportune time and free up f7 and still be up material due to the White Queen sac.

The question White has to answer is "How important is preventing ... h6?"

I can't see any variation where White wins if Black can play ... h6.

I can't see it; even the title isn't helping.

.

The keys were the weak back rank and also dark squares around the King.

• 1. Bxb6 removes one defender of c8 and wins a piece if Black fails to recapture
• 2. Qb5 attacks the Queen to try and dislodge it from defending c8
• 3. Rc8+:  with no defenders left of c8, checkmate follows
• 4. Rxf8+

2. Qb5 can be difficult to find due to ESSAS:  Empty Square Sac Avoidance Syndrome.  The observation that it's typically more difficult to see a sac when it involves no captures but instead places the piece on an empty square.

I found the solution but mis-evaluated the resultant position as not being favorable enough to White.  The engine states +4, which is obviously good enough, but I couldn't see that and so kept looking for a non-existent checkmate.  This was a failure of evaluation, not of calculation or visualization.  It's still a failure but it's good to know *how* one failed.

If this were a game, I likely would have played the correct solution since I couldn't find a conclusive checkmate ["A bird in the hand is worth two in the bush."].  But I approach puzzles differently.

Good mental workout!