Isodoku by John Bulten [Bonus]

Our subscribers receive access to bonus puzzles each week. We make these posts so those supporters have a space to comment on these puzzles, mark as FAVES, or log their solving. If you are interested in subscribing, click here for more info.

Isodoku by John Bulten

Theme: Cornered

Author/Opus: This is the 60th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Isodoku rules, using numbers 1-8.

Answer String: Enter the 2nd “row” from left to right, followed by a comma, followed by the 3rd “column” from top to bottom.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 8:30, Expert = 17:00

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

Killer Sudoku by Grant Fikes

Killer Sudoku by Grant Fikes

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 290th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Sudoku rules. Also, the sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.

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 = 9:00, Master = 15:00, Expert = 30:00

Solution: PDF

Note: Follow this link for other 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.

XV Sudoku by Ashish Kumar

XV Sudoku by Ashish Kumar

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 10th puzzle from guest contributor Ashish Kumar.

Rules: Standard Sudoku rules. Also, whenever the numbers in two adjacent cells sum to exactly 10 or 5, an X or V is placed on the edge between cells reflecting the Roman numerals for 10 or 5. All adjacent cells not marked with an X or V cannot add up to 10 or 5.

Answer String: Enter the 6th row from left to right, followed by a comma, followed by the 9th row from left to right.

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

Solution: PDF

Note: Follow this link for other 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.

Tight Fit (Unique) Sudoku by Serkan Yürekli

Tight Fit Sudoku by Serkan Yürekli

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku = big entries and Number candidate = small entries in the corners of cells.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 240th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Tight Fit Sudoku rules (in all slashed cells, a smaller digit must be placed above a larger digit). In this variation, all of the slashed cells must also have a unique pair of digits inside them.

Answer String: Enter the 3rd row from left to right, followed by a comma, followed by the 6th row from left to right. (Note: for the tight fit cells, enter the top before the bottom as would be normal for the read order.)

Time Standards (highlight to view): Grandmaster = 4:00, Master = 6:00, Expert = 12:00

Solution: PDF

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

Even/Odd Sudoku by Ashish Kumar

Even Odd Sudoku by Ashish Kumar

PDF

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

Theme: Boxing Day

Author/Opus: This is the 9th puzzle from guest contributor Ashish Kumar.

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 6th row from left to right, followed by a comma, followed by the 9th row from left to right.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 5:30, Expert = 11:00

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.

Star Battle Sudoku by Thomas Snyder

Star Battle Sudoku by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use the tab key to alternate between a Star Battle placement option and a Sudoku number entry option)

Theme: Christmas Tree

Author/Opus: This is the 331st puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Classic Sudoku rules, with the digits 1-7 and two stars to be placed in each row, column, and bold region. As in Star Battle puzzles, the stars cannot be placed in adjacent cells that share an edge or corner.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 9th row from left to right. Enter a capital letter X for any cell with a star in it.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:30, Expert = 9:00

Solution: PDF

Note: Follow this link for other 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.

Additional Note: This puzzle has been featured by the Cracking The Cryptic channel on Youtube.

Sudoku by Serkan Yürekli

Sudoku by Serkan Yürekli

PDF

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

Theme: No Parking

Author/Opus: This is the 239th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Sudoku rules.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 9th row from left to right.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 4:00, Expert = 8:00

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.

Tight Fit (Even/Odd) Sudoku by Serkan Yürekli [bonus]

Our master+ subscribers receive access to two bonus puzzles each week in addition to other rewards. We make these posts so those supporters have a space to comment on these puzzles, mark as FAVES, or log their solving. If you are interested in subscribing and seeing these bonus puzzles, click here for more info.

Tight Fit Sudoku by Serkan Yürekli

Theme: Twins

Author/Opus: This is the 238th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Tight Fit Sudoku rules. Also, digits within a gray square must be even and digits within a gray circle must be odd. The range of this puzzle is 1-9.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 4th row from left to right. (Note: for the tight fit cells, enter the top before the bottom as would be normal for the read order.)

Time Standards (highlight to view): Grandmaster = 1:40, Master = 2:45, Expert = 5:30

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

Schedule for Next Week

Our most recent variety mix of Spiral Galaxies puzzles can be found in this PDF.

Our last week of 2018 features Sudoku puzzles, particularly some less common variations spread across the week. This winter break is letting us complete the editing of The Art of Sudoku 2 and many more sudoku puzzles will be available on our e-store in the coming months.

This week, our subscribers are getting early access to the full week of puzzles and images of the puzzle solutions. Master+ subscribers to the site are getting a bonus Tight Fit (Even/Odd) Sudoku by Serkan Yürekli and an Isodoku by John Bulten. If you want to become a subscriber and get access to bonus puzzles, solutions, e-books, and other rewards, check out this page.

Double Spiral Galaxies by Thomas Snyder [Bonus]

Our subscribers receive access to bonus puzzles each week. We make these posts so those supporters have a space to comment on these puzzles, mark as FAVES, or log their solving. If you are interested in subscribing, click here for more info.

Spiral Galaxies by Thomas Snyder

Theme: 1, 2, 3, 4

Author/Opus: This is the 330th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Variation of Spiral Galaxies. In addition to the standard rules, some circles are shaded gray and must belong to galaxies containing two gray circles, not one, with the circles in rotationally symmetric spots for those galaxies.

Double Spiral Galaxies Example by Thomas Snyder

Answer String: Enter the number of cells in each connected group (between bold lines) in the marked rows. Separate each row’s entry from the next with a comma. The example has the answer “52,11131”.

Time Standards (highlight to view): Grandmaster = 4:45, Master = 8:30, Expert = 17:00

Note: Follow this link for classic Spiral Galaxies puzzles on this website and this link for variations on Spiral Galaxies puzzles. If you are new to this puzzle type, here are our easiest Spiral Galaxies Puzzles to get started on. More Spiral Galaxies puzzles can be found in The Art of Puzzles 2.