Latest Changes and Additions

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

Twinned XY-Chains
Date Created: Wednesday 14-May-2025
Last Updated: Wednesday 14-May-2025
Sudoku Twinned_XY_Chains invented by Nils Leder

Various Static Patterns
Date Created: Wednesday 14-May-2025
Last Updated: Wednesday 14-May-2025


20th Thank you
Date Created: Saturday 3-May-2025
Last Updated: Saturday 3-May-2025


Rule of 720 - With Divisors
Date Created: Thursday 1-May-2025
Last Updated: Thursday 1-May-2025


Not Allowed
Date Created: Monday 28-Apr-2025
Last Updated: Monday 28-Apr-2025
IFRAME embedding is not allowed

Innies and Outies
Date Created: Sunday 13-Apr-2008
Last Updated: Tuesday 22-Apr-2025
Killer Sudoku Strategy. An essential strategy for Killer Sudoku. It looks at the cells in cages which all inside or outside a unit or group of units. Since a unit must add up to 45 (in 9x9 Killer) overlaps can help remove candidates.

What's New
Date Created: Monday 17-Aug-2009
Last Updated: Tuesday 22-Apr-2025


Rule of 720
Date Created: Friday 28-Mar-2025
Last Updated: Tuesday 1-Apr-2025
Explains the Rule of 720 and how it is based on multiplication in the same way that the Rule of 21 is based on addition

Main Page
Date Created: Thursday 10-Apr-2008
Last Updated: Monday 17-Mar-2025
Strategies for Sudoku, Sudoku X, Killer Sudoku and Jigsaw Sudoku - and the home of logical puzzle maker Andrew Stuart

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Thursday 13-Mar-2025