Yin Yang

What is the Yin Yang rule?

Yin Yang is a variant sudoku rule: shade some cells so that all shaded cells are orthogonally connected, all unshaded cells are orthogonally connected, and no 2x2 area is entirely shaded or entirely unshaded.

In every puzzle here the setter’s own rules text is shown beside the board, so the exact wording for the puzzle you are solving is always one glance away. All normal sudoku rules apply unless the setter says otherwise.