Finned Swordfish

A Swordfish with an in-box fin — and its Sashimi degenerate form.

Learn the Finned Swordfish technique (with Sashimi): a 3-line fish with an in-box fin, so the digit is cut only from cells that see both the fish and the fin.

How to use it

1. Find the almost Swordfish. Find three rows (or columns) that nearly confine a digit to three lines, save for a fin of one or two extra spots that all sit in a single box.
2. Handle the fin (and Sashimi). If the fin is empty the Swordfish is real; if it holds the digit, the digit lands in the fin’s box. Sashimi is the same idea when the fin props up an otherwise-incomplete line.
3. Cut only where both apply. Remove the digit only from cells the basic Swordfish would clear that also see every fin cell — typically the cover cell sharing the fin’s box.