PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku number entry mode and a shading mode to manage the shape inventory.)

Theme: Zero X

Author/Opus: This is the 56th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Shape Sudoku rules.

Answer String: Enter the 2nd column from top to bottom, followed by a comma, followed by the 5th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 3:30, Expert = 7:00

Solution: PDF

Note: Follow this link for other less common variations of Sudoku. Many specific variations of Sudoku have their own categories in the sidebar to the left. Follow this link for classic Sudoku.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Sudoku GP Round 7 (this puzzle continues a hidden theme present throughout Prasanna’s Sudoku Grand Prix set)

Author/Opus: This is the 41st puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Sudoku rules. Additionally, all cells having the same digit(s) more than once as orthogonal neighbors are shaded. (If a cell is not shaded, it cannot have any digits repeated as orthogonal neighbors). Or see this example image.

Answer String: Enter the 8th row from left to right, followed by a comma, followed by the 2nd column from top to bottom.

Time Standards (highlight to view): Grandmaster = 9:00, Master = 17:30, Expert = 35:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other less common variations of Sudoku and this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Two-Sided Problem

Author/Opus: This is the 187th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Even/Odd Sudoku rules (i.e., cells with a square contain an even digit; cells with a circle contain an odd digit).

Answer String: Enter the 4th row from left to right, followed by a comma, followed by the 2nd column from top to bottom.

Time Standards (highlight to view): Grandmaster = 3:45, Master = 8:00, Expert = 16:00

Solution: PDF

Note: Follow this link for more Even/Odd Sudoku puzzles. If you are new to this puzzle type, here are our easiest Even/Odd Sudoku to get started on. More Even/Odd Sudoku puzzles can be found in The Art of Sudoku 2.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 186th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 7th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:15, Expert = 8:30

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Fortress

Author/Opus: This is the 4th puzzle from guest contributor Craig Kasper, who has recently started a new blog about puzzles.

Rules: Standard Consecutive Sudoku rules.

Answer String: Enter the 6th row from left to right, followed by a comma, followed by the 6th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 4:45, Expert = 9:30

Solution: PDF

Note: Follow this link for other Consecutive Sudoku. If you are new to this puzzle type, here are our easiest Consecutive Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Four Arrows

Author/Opus: This is the 185th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 5th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 3:45, Expert = 7:30

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Counting Puzzle?

Author/Opus: This is the 184th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Deficit Sudoku rules.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 4th row from left to right.

Time Standards (highlight to view): Grandmaster = 1:20, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for other Deficit and Surplus Sudoku.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Sudoku GP Round 7, plus two hidden themes related to 7
(Note: this puzzle was originally created for the Sudoku Grand Prix but after testing was judged too hard and too puzzle-based for the competition. It is an excellent puzzle, and we are proud to showcase it here.)

Author/Opus: This is the 40th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Sudoku rules. Also, standard Skyscrapers rules. Additionally, the cells in gray are “underground” and cannot be seen by any of the outside skyscraper clues (think of them as starting with a negative sign if necessary). As an example, the 3 on the left of row 2 refers only to seeing three buildings in columns 2 through 9, even if there is a 9 in column 1 as that 9 cannot be seen.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 10:00, Expert = 20:00

Solution: PDF

Note: Follow this link for our first Basement Skyscraper Sudoku. Follow this link for other less common variations of Sudoku and this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 54th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Sudoku rules. Every given clue is lying. The correct value is either one more or one less than the given clue. (1 clues cannot become 0, and 9 clues cannot become 10.)

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 5:30, Master = 8:00, Expert = 16:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Diamonds

Author/Opus: This is the 182nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 9th row from left to right, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 2:20, Master = 3:30, Expert = 7:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.