Jigsaw Sudoku
Follow the outline, then the numbers
Jigsaw keeps the usual row and column rules, but replaces square boxes with nine irregular regions. Each outlined region contains nine cells and needs every digit from 1–9 once. The printed borders define which cells belong together.
01
Trace one whole region first
Follow its border around all nine cells before checking candidates. A bent region may cross several rows; an imagined 3×3 square supplies no constraint.
02
Ask where one digit fits
Check the missing digits within that exact region. If row and column restrictions leave only one possible cell for a digit, its position is proved.
03
Use a shared row carefully
If all possible positions for a region’s digit lie in one row, remove that digit from the rest of that row, outside the region.