Tolling

In this puzzle you get to create a river for Nala and tag along with her while she is alternately playing and hiding along the shoreline! This special kind of behaviour known as 'tolling' is very typical for her fathers breed: The Nova Scotia Duck Tolling Retriever. It is meant to get ducks curious so they will swim closer to the shore and is very interesting thing to experience. Join us!

Part 1: The River Using the clues outside the grid shade some cells to form a river (blue clues) such that all shaded cells are orthogonally connected and no 2x2 is entirely shaded. The rest of the cells are the unshaded shoreline (green clues).

If a clue has a number in it, that number indicates how many cells of that color are shaded in the direction the clue is looking at (row or column). If a clue has no number in it, the amount of shaded or unshaded cells has to be deduced by the solver, but cannot be 0.

All clues are given and in order. In the final grid all cells are either blue or green.

Part 2: Tolling Use the shaded grid to solve the Sudoku as Nala is tolling alongside the shoreline.

Normal 9x9 Sudoku rules apply: Place the digits 1-9 in every row, column and box exactly once each.

The grid is partially covered in fog. Placing correct digits will clear the fog from surrounding cells, possibly revealing more clues.

Digits along an arrow must sum to the digit in the corresponding circle. Arrows do not cross or overlap.

Digits separated by a white dot are consecutive.

The river functions as an entropic line. Any set of three sequential cells along the river must contain a low digit (123), a middle digit (456), and a high digit (789).