Latest Changes and Additions

A quick list of the latest updates and additions to this site:

Intersection Removal
Date Created: Thursday 3-Apr-2008
Last Updated: Monday 22-Jun-2026
Sudoku Strategy. Pointing Pairs and Box Line Reduction are two Intersection Removal strategies used to eliminate candidates in the boxes that intersect the row or column that the formation lies on.

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Sunday 14-Jun-2026


Naked Candidates
Date Created: Thursday 9-Jun-2005
Last Updated: Monday 8-Jun-2026
Sudoku Strategy. Naked Pairs, Triples and so on - these are the remaining candidates left in cells aligned on a row, column and box which can be used to remove other candidates the formation is aligned with.

Cell Forcing Chains
Date Created: Saturday 6-Mar-2010
Last Updated: Sunday 7-Jun-2026
Sudoku Strategy. This is a Forcing Chains Strategy. It finds eliminations by comparing the results of two chains starting with a bi-value cell assuming either candidate in the cell is turned on.

Unit Forcing Chains
Date Created: Saturday 6-Mar-2010
Last Updated: Sunday 7-Jun-2026
Sudoku Strategy. This is a Forcing Chains Strategy. It finds eliminations by comparing the results of chains starting with all candidates N in a unit and assuming any of them are turned on.

Digit Forcing Chains
Date Created: Wednesday 17-Mar-2010
Last Updated: Saturday 6-Jun-2026
Sudoku Strategy. This is the start of a family of strategies called Forcing Chains. It finds eliminations by comparing the results of two chains starting with a single digit - that digit being on or off.

Rectangle Elimination
Date Created: Saturday 7-Oct-2023
Last Updated: Friday 5-Jun-2026
A new tough strategy by Ken Reek

AIC with Groups
Date Created: Saturday 12-Apr-2008
Last Updated: Monday 1-Jun-2026
Sudoku Strategy.Alternating Inference Chains can take advantage of grouped cells to make links. This article explains how.

Bowman's Bingo
Date Created: Saturday 2-May-2026
Last Updated: Saturday 2-May-2026


Forcing Nets
Date Created: Monday 9-Mar-2026
Last Updated: Monday 6-Apr-2026
Explanation of Forcing Nets - an expansion of Forcing Chains using Alternating Inference Chains.