Monkeymore Sudoku

Finned Squirmbag

Level 11 · Red Belt

Prerequisite: Finned & Sashimi FishLearn next → Finned JellyfishLearn next → Squirmbag

Overview

A Finned Squirmbag is a Squirmbag (5-fish) pattern with extra candidates forming a fin. This is one of the rarest patterns in Sudoku solving.

How It Works

  1. Find a Squirmbag where one row has candidates outside the five columns.
  2. These extra cells are the fin.
  3. Eliminations occur only in cells seeing both the cover columns and the fin.

Example

Base rows 1, 5, 6, 8 and 9 form a Squirmbag for digit 8 in cover columns 2, 6, 7, 8 and 9.

1 / 23

Tips & Patterns

  • Finned Squirmbags are almost never needed in human-solvable puzzles.
  • This is primarily of theoretical interest.