2025/10/02 DPA: "Go Ahead: Take My Bishop!"

White to move:

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Black's Bishop is en prise.

But I take it, Black can play 1. ... Rg5+, winning my Bishop.

If my Rook was on b1, I could play 1. Rb8+, skewering the King but that won't win because the Rook is protected by the Bishop.  I'd have to take the Bishop and then get my Rook to b8.  Too slow.

If I play 1. h4 to prevent 1. ... Rg5+, that just gives his Bishop time to move out of harm's way.

Is there a checkmate opportunity?   I'd have to get my King to d6 and get my Rook to the b or f file; meanwhile, Black could check and dislodge me from d6.

Using the Rook for anything else besides 1. Rxc4 does not seem to lead anywhere.

So 1. Rxc4 must be the first move but what to do after 1. ... Rg5+ and 2. ... Rxh5?  Now my h pawn is en prise, which I can protect with 3. h4 but that's defense.  There has to be something offensive.

I do threaten 4. Kg6, attacking the Rook and when the Rook leaves, 5. Kxh6; but Black will play 3. ... Rd5 then 4. ... Rg6+, protecting the pawn.

And even a pawn up, that might not be a winning endgame.

Hmm, I see something:  even though the Black Rook has the entire 5th rank, certain squares are off-limits.  If White moves 2. Ke6, every square will be controlled or blocked.

Neither Black pawn can move.

The Black King can only move to e8, which allows 4. Rc8#.

So he has to move the Rook and there's nowhere to go.

That was it:

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The general key was recognizing the possibility of Zugzwang.  It only occurred to me after I had tried to visualize other solutions.  I didn't have it in mind at the outset.

The only part that required calculation was figuring out which square to move the King to after the check:  it must be to e6 so every square is accounted for:  if it moved to f6, that would have left d5 uncovered.

And the Solver had to see that prior to moving 3. h4.

Tricky one by our MPC [Master Puzzle Creator] @JohanVA!