Sudoku - Hard

These hard sudoku puzzles have fewer clues than the others on the site and will require more advanced strategies to solve.

Train your brain with the 175 Large Print Hard Sudoku Puzzles for Adults 6x9 activity book! With 175 large print hard Sudoku puzzles at your

175 Large Print Hard Sudoku Puzzles for Adults: Only One Puzzle Per Page! (Pocket 6x9 Size) (Paperback)

Samurai Sudoku - Hard

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Sudoku - Hard A3 Printable Puzzle

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Hard Sudoku: Huge 300 hard SUDOKU puzzle books - sudoku hard to extreme difficulty Maths Book to Challenge Your Brain for Adult and (Large Print / Paperback)

Can You Solve the Hardest-Ever Sudoku? - ABC News

Butterfly Sudoku - Hard

Free Printable Hard Sudoku with the Answer #14739

[Robbins, Rebecca] on . *FREE* shipping on qualifying offers. Sudoku: 400+ Sudoku Puzzles with Easy, Medium, Hard, and Very Hard

Sudoku: 400+ Sudoku Puzzles with Easy, Medium, Hard, and Very Hard Difficulty Levels (Sudoku Puzzle Book)

Sudoku Hard - Free Web Sudoku 247

Large Print Sudoku Puzzles Red Book #5 (Hard) : Hard Sudoku Puzzle Book including Instructions and Answer Keys (Paperback)