Tutorial #80 A difficult sudoku puzzle made easy

Tutorial 58. Hard sudoku puzzle with lots of techniques.

Lesson 1 Learn sudoku. How to solve sudoku for beginners. Horizontal blocks using TMB.

Tutorial # 47 More tricks using logic.

Tutorial #66 have found many of these lately. Unique rectangle, Danger Danger.

Tutorial #54 The finned Xwing. Using rows.

Tutorial #40 A must know technique. NOT a puzzle.

Tutorial #56. A difficult puzzle solved from beginning to end. Lots to learn.

Tutorial #50 Solving a hard puzzle from the beginning to the end