Latest Changes and Additions

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

Cage Unit Overlap
Date Created: Tuesday 22-Mar-2011
Last Updated: Tuesday 27-Oct-2026
Killer Sudoku Strategy. Cage Unit Overlap looks at the intersection of a cage with a row, column or box to find eliminations.

Captured Candidates
Date Created: Tuesday 27-Oct-2026
Last Updated: Tuesday 27-Oct-2026
A Killer Sudoku Strategy

3D Medusa
Date Created: Saturday 6-Mar-2010
Last Updated: Friday 23-Oct-2026
Sudoku Strategy. 3D Medusa takes chain building into all the dimensions of the Sudoku board. That is, by making links among rows, columns and boxes - and in bi-value cells. Many types of eliminations are possible with this network approach.

Tridagons
Date Created: Friday 19-Sep-2025
Last Updated: Monday 19-Oct-2026
The Tridagon or Thor's Hammer is a Sudoku strategy discovered by Denis Berthier

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Monday 19-Oct-2026


Unique Rectangles
Date Created: Friday 11-Apr-2008
Last Updated: Thursday 15-Oct-2026
Sudoku Strategy. Unique Rectangles takes advantage of the fact that published Sudokus have only one solution. There are many formations and strategies based on this notion and they are explained here.

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Thursday 3-Sep-2026


Simple Colouring
Date Created: Saturday 29-Jan-2011
Last Updated: Saturday 4-Jul-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.

Rectangle Elimination
Date Created: Saturday 7-Oct-2023
Last Updated: Thursday 2-Jul-2026
A new tough strategy by Ken Reek

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.