Latest Changes and Additions

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

Digit Forcing Chains
Date Created: Wednesday 17-Mar-2010
Last Updated: Friday 5-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.

Naked Candidates
Date Created: Thursday 9-Jun-2005
Last Updated: Friday 5-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.

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.

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


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.

Simple Colouring
Date Created: Saturday 29-Jan-2011
Last Updated: Saturday 4-Apr-2026
Sudoku Strategy. Single's Chains, also known as Simple Colouring is a chaining strategy and part of a large family of such strategies. Cells and units with only two remaining candidates N are used to make links and find contradictions.

BUG
Date Created: Friday 11-Apr-2008
Last Updated: Monday 9-Mar-2026
Sudoku Strategy. BUG stands for Bi-Value Universal Grave. It is a formation that relies on the uniqueness of the solution and an array of bi-value cells.

Cell Forcing Chains
Date Created: Saturday 6-Mar-2010
Last Updated: Monday 2-Mar-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.