These puzzles are not dressed to the “9’s”! That’s because not one of these sudoku contains the number 9 as a given, so solvers must do some mining to discover where they belong. Pixel-y, nerdy, creative, and challenging, Ninecraft Sudoku features nearly 190 puzzles that get harder as you go along, and includes some grids with givens that are in shapes seen in mining games.
Mr. Riley is a software developer at Fairfield Language Technologies, and the author of numerous computer programs that analyze variants of sudoku puzzles. Dr. Taalman is a professor of mathematics at James Madison University. Her research interests include singular algebraic geometry, knot theory, and open questions about the mathematics of sudoku and other puzzles.