2023/09/10 DPA: "Best supporting actress in a dramatic checkmate goes to...the Queen"

Black threatens checkmate in two ways:  ... Qf2# and Qh1# [note that, even if White could eliminate the a2 Rook, Black still has ... Qh1# due to the Bishop on g4].

Another open board King Hunt.  Gotta make sure every check does not allow the King to slip through the mating net.  White must continually restrict Black's movements until the very end.

1. Nf5 is promising since 1. ... Bxf5 [otherwise, White gets a Royal Fork]  2. Bxf5 discovered + [by the Rook] Kd6 but there is no follow-up:  White's Queen is still stuck as all of the attacking squares are covered [f8 is covered by the Knight, the b8 Bishop is covered by the Knight, the Knight is protected by the Rook and the g4 Bishop, etc].  3. Nb5+ Kc6  4. Rc1+ Kb6 and White has run out of checks, as 5. Qd8+ is met with Bc7 and Black threatens White's Queen AND checkmate.

1. Ned5+ Kd6  2. Nb5+ Kc6  3. Nxb4++ [double-check by the Knight and Bishop] Kxb5 and I couldn't see a way forward.  White must be careful of sacing too many pieces to give check.

1. Ncd5+

Ke6  2. Qe8+

Kd6 [if 2. ... Qe7  3. Qxe7+]  3. Nc4+

Kc6.  Here I got stuck because 4. Nxb4++ didn't lead anywhere after 4. ... Kb5.

Eventually, I found 4. Nc3 discovered +:  non-intuitive because A) White is moving the Knight back to its starting square; and B) the Knight is now en prise.

But this is exactly what is needed.  It's irrelevant that the Knight is hanging because it's not the piece giving check.

4. ... Kc7 [all other squares are covered] 

5. Nb5#.

I had to quadruple check [no pun intended] those last 2 moves to make absolutely sure I wasn't leaving a hole in the net.

Note that the Queen did give one check and protected the back rank but, for the most part, the heavy lifting was done by the light [minor] pieces.

This took about 90 minutes to work out since 1. Ncd5+ was the last of the 3 checks I analyzed.