Logic Masters Deutschland e.V.

Here is the full size puzzle I made with this ruleset, following the small one I published here previously. If you are not familiar with the way of solving this, I encourage you to try this small puzzle before, or take a look at the diagram (with 2x2 regions) at the bottom of this page, demonstrating the rules and suggesting ways of notating the deconstruction (cages, circles, crosses) to avoid a confusing double coloring with the cave shading.

The puzzle :

Play on Penpa

Play on Sudokupad

Rules :

- Normal sudoku deconstruction apply : Fill the grid with 9 non-overlapping 3x3 square regions, such that each region contains the digits 1-9 once each and no digit repeats in any row or column. Cells outside regions do not contain digits.

- Narrow Cave : the whole 11x11 grid must form a valid cave : shade some cells in the grid so that all shaded cells (the walls) are orthogonally connected to the edge of the grid, and all unshaded cells (the cave) form an orthogonally connected area. No 2x2 block may be entirely unshaded.

- Clues : numbers in the top left corner of a cell are ambiguous clues.

- If a clue is in an unshaded cell (cave), it indicates the sum of the digits that are seen in all orthogonal directions from this cell. The cell with the clue counts once in this sum. Walls obstruct the view. Within the field of vision of a clue, digits may not repeat.

- If the clue is in a shaded cell (wall), it indicates the number of cells of that area of orthogonally connected shaded cells. There can be any amount of clues in each area of orthogonally connected shaded cells, including none.

Diagram of a deconstruction inside a narrow cave grid :