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Sudoku How To Technique: Squirmbag

Taking Jelly-Fish to the next level by adding an additional number of valid ROWS and COLUMNS form four to fove. What you need to look for is a VALID HINT that shows five or less times within a primary ROW or COLUMN that share the same four alternate ROW or COLUMNS. To be valid the HINT cannot show up more than five times within the primary ROW or COLUMN. It can show up more than five times within the alternate ROW or COLUMN or we wouldn’t have anything to eliminate.

Reviewing the example, the primary COLUMNS C1, C2, C6, C7 and C9 have a HINT value of {3}, that share the secondary ROW CONTAINER. Because of that, we are safe to remove the HINT value of {3} anywhere else on the secondary container. Think of the primary container as “safe cells”, and you do not remove hints from those.

If looking for solutions for cells manually, I would not recommend trying to look for this type of hint reduction method. Other solution patterns will most likely show a positive before this one.

This solving method has been categorized as Very Hard Sudoku. Try this and other Very Hard Sudoku solving methods.
Try this Squirmbag Sudoku puzzle.

Puzzle Number: 1262222
Method: SQUIRMBAG {3} - In Block Type: COLUMN
Found Cell and Hints: s1r3c1 3; s1r5c1 3; s1r6c1 3; s1r2c2 3; s1r3c2 3; s1r5c2 3; s1r6c2 3; s1r1c6 3; s1r3c6 3; s1r1c7 3; s1r2c7 3; s1r6c7 3; s1r1c9 3; s1r2c9 3; s1r3c9 3; s1r5c9 3; s1r6c9 3;
Removing Hints: s1r1c5 3; s1r2c5 3;

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