Free jigsaw, thermo, kropki and anti-knight sudoku
Four sudokus where the grid itself carries the extra rule. Quilt redraws the boxes as crooked regions. Mercury draws thermometers that rise from the bulb. Polka puts dots between cells whose digits are consecutive or doubled, and a missing dot means neither. Knight forbids two of the same digit a chess knight’s move apart.
Quilt is the gentlest step into variants: only the shape of the boxes changes. Mercury adds ordering, digits increasing along every thermometer. Polka is kropki: a white dot means consecutive, a black dot means one is double the other, and where there is no dot, neither is true. Knight keeps every classic rule and adds one: no digit may repeat a knight’s move away.
Yes. Where two cells have no dot, their digits are neither consecutive nor one double the other. That negative clue does much of the work.
All four, every day, no account required.