Wings
How it works
A Y-Wing whose pivot carries three candidates instead of two: a pivot holding X, Y and Z with pincers X-Z and Y-Z that it can see. Z now has to land in one of three cells rather than one of two, which makes it harder to spot and narrows the payoff — only a cell seeing all three, pivot included, can have Z eliminated.
Try it
Look at Row 4, Column 6, Row 4, Column 7, and Row 6, Column 6 — a three-candidate pivot and two cells it can see. Let's pencil them in, then see why 3 can't survive where all three overlap.
9
3
6
5
7
1
8
2
4
1
5
8
4
2
9
7
3
6
7
4
2
6
9
5
1
2
8
7
1
7
2
4
6
9
2
8
7
6
2
3
1
4
7
5
9
8
9
8
6
2
1
7
3
8
1
7
3
9
5
4
6
2