WPC 2023/Round 13

Duration: 70 minutes. Total point value: 700 points. Round winner: Walker Anderson (USA), 1040 points.

Puzzles

All puzzles in this round are shading puzzles that involve a different set of rules, based on the puzzle game Islands of Insight.

1. Islands of Insight by Elyot Grant, 40 points
2. Islands of Insight by Elyot Grant, 45 points
3. Islands of Insight by Jamie Hargrove, 60 points
4. Islands of Insight by Jamie Hargrove, 60 points
5. Islands of Insight by Elyot Grant, 90 points
6. Islands of Insight by Jamie Hargrove, 70 points
7. Islands of Insight by Elyot Grant, 110 points
8. Islands of Insight by Jamie Hargrove, 85 points
9. Islands of Insight by Elyot Grant, 140 points

From the IB:

"There are four types of symbols that may be included in the grids:

1. Numbers: Cells containing numbers must always remain unshaded. Numbers indicate the total number of unshaded cells that can be seen in a straight line vertically and horizontally from the numbered cell, including the cell itself.
2. Letters: Cells containing letters must always remain unshaded. If two or more letters are the same, they must lie in the same unshaded region. If two letters are different, they must lie in different unshaded regions.
3. Black and White Circles: Black circles indicate shaded cells; white circles indicate unshaded cells.
4. Mirror Symmetry Symbols: Cells containing these symbols must remain unshaded. There are four kinds of mirror symmetry symbols: horizontal, vertical, and both diagonals. An unshaded region containing a symmetry symbol must be mirror-symmetric, with the axis of symmetry passing through the symbol and matching its orientation. Only the shape of the region needs to be symmetric (the positions of symbols such as numbers and letters are ignored when determining symmetry). If a region contains multiple symmetry symbols, it must exhibit a symmetry for each of them.

There are four types of constraints that may be included above the grids:

1. All shaded cells are connected. In puzzles where this constraint is included, all shaded cells in the grid must be orthogonally connected.
2. All unshaded cells are connected. In puzzles where this constraint is included, all unshaded cells in the grid must be orthogonally connected.
3. All shaded regions have area N. In puzzles where this constraint is included, all shaded regionsmust consist of exactly N orthogonally connected cells. N may be any positive integer and may be different in different puzzles.
4. Don’t make this pattern. This constraint will be accompanied by a small grid illustrating a forbidden pattern. Forbidden patterns consist of white squares (indicating unshaded cells), black squares (indicating shaded cells), and empty cells (indicating “don’t cares”). Forbidden patterns may not occur in the solution to the puzzle. For example, a 2×2 region of shaded cells being forbidden is similar to Tapa or Nurikabe. Reflections and rotations of forbidden patterns are also forbidden."