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

Extended Unique Rectangles
Date Created: Friday 24-Aug-2012
Last Updated: Saturday 11-Jun-2022
Discussion of Extended Unique Rectangles taking 2x2 Unique Rectangles to 3x2

Date Created: Friday 11-Apr-2008
Last Updated: Monday 27-Dec-2021
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.

Almost Locked Pair
Date Created: Monday 27-Dec-2021
Last Updated: Monday 27-Dec-2021
Almost Locked Pair and Triple strategy

Date Created: Sunday 12-Dec-2021
Last Updated: Sunday 19-Dec-2021
Sudoku Fireworks Strategy invented by Shye

Date Created: Wednesday 3-Nov-2021
Last Updated: Wednesday 3-Nov-2021
Glossary of Sudoku Terms

Cage Unit Overlap
Date Created: Tuesday 22-Mar-2011
Last Updated: Friday 23-Jul-2021
Killer Sudoku Strategy. Cage Unit Overlap looks at the intersection of a cage with a row, column or box to find eliminations.

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Tuesday 13-Jul-2021

Date Created: Wednesday 26-Oct-2016
Last Updated: Friday 2-Jul-2021

Double BUG
Date Created: Thursday 20-May-2021
Last Updated: Thursday 20-May-2021
An investigation into the potential of BUG by John Libbey

Unique Rectangles
Date Created: Friday 11-Apr-2008
Last Updated: Saturday 30-Jan-2021
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.