2025/06/08 DPA: "Measure Twice, Cut Once"

White to move.

Looks like a classic Smothered Mate:  but I failed to see the pin of the Queen and so played 1. Qe5+ Ka8  2. Nc7+ Kb8  3. Na6^++ [discovered check, double check], which is wrong:  the Solver must first take out the Rook so that the Queen can deliver the penultimate check without exposing the King to check:  3. Nxe8^ Ka8  4. Nc7+ Kb8  5. Na6^++ Ka8  6. Qb8+ Rxb8  7. Nc7#.

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For those unfamiliar with the Smothered Mate pattern, you check with the Queen with the Knight already in place so if 1. ... Kc8  2. Qc7#.

The King retreats into the corner and the Knight follows up with a check.  The King must return to b8.

The typical pattern is 3. Na6^++, which is a discovered check by the Queen and a check with the Knight so neither piece can be captured and the King must retreat again.

If you don't know this pattern, you will simply play Nc7+ again and draw.  But ... Qb8+ is the correct move, because the King cannot capture due to the Knight's protection.  So the Rook must capture, which sets up the Smothered Mate.

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I was careless:  I saw a familiar pattern and just blindly chose it rather than looking more closely, especially since this is a Sunday so it should be more difficult.

Another thing that made this trickier:  the deviation came on the 3rd move, so I had already made 2 moves and felt comfortable that I was on the right path.  This was probably deliberate by the puzzle creator.

Nicely done, @JohanVA!