Logic Puzzle Pro

How to complete Logic Puzzle Pro

A hard Sudoku is pure deductive logic with no luck involved, and finishing one unaided proves you can hold a chain of constraints in your head and follow it to the end. The 'no looking up answers' rule is the whole point: the satisfaction and the skill both come from grinding through the stuck moments yourself.

1. Get a puzzle explicitly rated hard, expert, or evil, not easy or medium
2. Fill in every obvious single-candidate cell first to thin the field
3. Pencil in candidate numbers for the trickier cells in the corners
4. Work techniques like naked pairs, pointing pairs, and hidden singles to eliminate options
5. Push through stuck points by scanning rows, columns, and boxes for the one forced number

Tips

• Never guess; if you're guessing, you've missed a logical step, back up and re-scan
• A clean grid with neat pencil marks prevents the careless errors that ruin late-game
• Apps that flag mistakes count as looking up answers; use plain paper or a no-hint mode

What counts as done

The grid is fully and correctly filled with every row, column, and box holding 1-9, done without hints or solvers.