The last two closing puzzles of the World Sudoku Championship playoffs were very tricky, starting with this hybrid of Clone and Shape Sudoku by Joseph Howard.
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Theme: 8 Rings
Author/Opus: This is the 33rd puzzle from guest contributor Joseph Howard.
Rules: Combination of Shape and Clone Sudoku rules. Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. Also, there are some numbered shapes that must be put into the grid. Shapes can be rotated, but cannot be reflected. Each shape outside the grid must appear exactly once inside the grid. Also, all remaining shaded regions of the same shape (“clones”) must be able to be paired together to include the same numbers in the same positions.
Estimated Difficulty: 3.5 stars
Solution: PDF for all playoff puzzles.
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