[This is a repost from our archives with new notes at the top (original post here): My first experience with Deficit Sudoku, originally from Wei-Hwa Huang and named “Udoku”, was at the second World Sudoku Championship in Prague. By the time we wrote the style into our Mutant Sudoku book, we had renamed the variation to Deficit Sudoku. This theme recalls a special challenge Wei-Hwa made in that first set using the digits 0-9; in this case, I could make a similar think outside the box theme with just 1-7, keeping the 7 as an unseen number.]
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Theme: Not Your Standard 6×6 Sudoku! An homage to my favorite (10×10) puzzle from the original “Udoku” set of Deficit Sudoku by Wei-Hwa Huang.
Estimated Difficulty*: 2 stars
Time Standards (highlight to view): Grandmaster = 1:00, Master = 2:00, Expert = 4:00