Tip 1
Find the loner
The digit that appears once, hiding at the intersection of the only row and column that name it.
Try it on the play pageTips & Tricks
Four short animations covering the core solving techniques. Watch them, then give them a try on the play page.
Tip 2
Third placement reveals itself
Once a digit is on the board twice, the remaining row + column lock the third placement to one cell.
Try it on the play pageTip 3
Center cell, four constraints
C3 sits on its row, its column, and both long diagonals — usually the easiest cell to solve second.
Try it on the play pageTip 4
Diagonals as tiebreakers
When row + column leave you with two candidates, the long diagonal is the constraint that breaks the tie.
Try it on the play pageBrowser demo
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