Two rules, one calm grid
Each thickly outlined pool holds 1 to its size, once each. A four-square pool needs 1, 2, 3 and 4.
Equal numbers in the same row or column need space: two 2s need at least two squares between them. Those squares can hold other numbers.
2··2Two intervening squares: allowed
In general, two ks need at least k intervening squares. Diagonals do not count. Pool borders do not stop the ripple.
Select a square, then choose a number. Gold outlines show where that same number is too close. Blue shading shows the selected pool.
Pinned numbers (◆) stay fixed. Conflicts may appear while you experiment; undo and erase are always available.
