Latest Changes and Additions

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

Innies and Outies
Date Created: Sunday 13-Apr-2008
Last Updated: Thursday 28-Aug-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.

Finned Swordfish
Date Created: Saturday 12-Apr-2008
Last Updated: Wednesday 27-Aug-2025
Sudoku Strategy. Finned Sword-Fish extends the Sword-Fish strategy but it has extra candidates of X that prevent one of the three trios normally required. Eliminations are still possible in this fin.

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


WXYZ-Wing
Date Created: Friday 11-Apr-2008
Last Updated: Sunday 17-Aug-2025
Sudoku Strategy. WXYZ-Wings extend XYZ-Wings to four numbers and are four cell formations used to eliminate candidate elsewhere. They use a common candidate method to find contradictions.

3D Medusa
Date Created: Saturday 6-Mar-2010
Last Updated: Thursday 14-Aug-2025
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.

XY-Chains
Date Created: Friday 11-Apr-2008
Last Updated: Wednesday 13-Aug-2025
Sudoku Strategy. XY-Chains are the work-horse of chaining strategies and are very easy to use when the board contains many bi-value cells. When the start and end cells can see a common candidate eliminations can be made.

Donations
Date Created: Saturday 12-Apr-2008
Last Updated: Saturday 26-Jul-2025


Test Strings
Date Created: Wednesday 20-Nov-2024
Last Updated: Saturday 19-Jul-2025


Daily Binairo Plus (6x6)
Date Created: Monday 14-Jul-2025
Last Updated: Monday 14-Jul-2025


Daily Binairo Plus (8x8)
Date Created: Monday 14-Jul-2025
Last Updated: Monday 14-Jul-2025