by Jakhob and wooferzfg

Normal Irregular Sudoku rules apply, but the regions must be determined by the solver. All regions are orthogonally connected groups of 9 cells.

A digit in a circle indicates how many region borders between the 9 surrounding cells touch the region which contains the cell with the circle. The edge of the grid does not count towards the total.

A digit in a square indicates how many of the 9 surrounding cells (including itself) belong to the same region as the cell with the square.

Not all circles and squares are necessarily given.


Here are examples of valid circle and square clues:

Puzzle Links

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