21:34

2 Sudoku TIPS That Changed My Life For The Better – SHC 256

27:37

My Honest Advice To Someone Who Wants To Solve Hard Sudoku

15:59

This AMAZING Trick Can Solve Extreme Sudoku

6:08

A Sudoku Secret to Blow Your Mind - Numberphile

23:33

OPTIMAL Order Of Solving Very Hard Sudoku