Diagonal Clue Pair
Hard
Used by Smart Hint
Two clued cells touching only at a corner still constrain each other through that shared dot — any side no valid combination uses is forced.
- Cells that establish the pattern
How it works
- These two cells only touch at a single shared dot — they don't share an edge directly.
- But that shared dot still needs degree 0 or 2, and its 4 edges are exactly these two cells' own edges (2 each) — so the same "try every combination, see what always/never happens" check from Adjacent Clue Pair still applies here.
- The two named shapes below — Diagonal 3s and 3 Diagonally Opposite a 0 — are what this finds most often. The same reasoning, chained further across the board, is what recovers longer "Diagonal 2s" relationships too (see Region Coloring).