14:06

dxSudoku #27 Skyscraper Puzzle Solving Technique

12:41

dxSudoku #56 Hidden Rectangle

12:52

dxSudoku #6 Hidden Pairs

15:32

dxSudoku #57 Naked Quad

6:47

Making a Hard Sudoku really easy

10:18

Tutorial #68 Strong and Weak links and Open Ended Chains, which enable you to remove small numbers.

3:27

20 Sudoku Strong Weak Links

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Top Nine Most Often Used Strategies for Solving Expert Sudoku Puzzles