Sudoku by Thomas Snyder

[This puzzle comes from the 2022 US Sudoku Grand Prix round written entirely by me. This puzzle demonstrates another visual approach to an “eight” theme. While there are no 8s in the grid, all the givens appear in clear two by four block groups which is a pattern that sets up some nice if easy geometric deductions.]

Sudoku by Thomas Snyder

PDF

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

Theme: Two by Fours

Author/Opus: This is the 431st puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Estimated Difficulty: 2 stars

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 our e-store, including in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Sudoku by Thomas Snyder

[This puzzle comes from the 2022 Sudoku Grand Prix round written by me, which was the eighth round that ran in early August including 8/8. The round used a theme of “eight” across all the puzzles. This easy classic Sudoku has a strong visual theme with just three given digits, two eights in the corners and a big “eight” made out of other numbers only.]

Sudoku by Thomas Snyder

PDF

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

Theme: Three Eights

Author/Opus: This is the 430th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Estimated Difficulty: 2 stars

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 our e-store, including in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Sunday Update

Our tenth Smashing the Sudoku video, finishing our original 60+1 puzzle reposting series is now live:

We’re still working on setting up an initial version for a GMPuzzles subscription/release model leveraging Discord. If you are interested in being a tester and committing to adding comments/sharing feedback, please let me us know at ads@gmpuzzles.com. We will likely have an email option to share the content to subscribers as well, but right now we are looking for testers to tell us if a Discord integration (as an early version of a more fully fledged platform) is worth committing more time to.

We’ll be posting Sudoku from our 2022 Sudoku Grand Prix Round over the next couple weeks.

Fillomino by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): The final puzzle of our first sixty set, this Fillomino takes advantage of several less common look-ahead steps to make progress towards the solution. While I hadn’t constructed as many Fillomino before in my life, I learned a lot from this week of experimentation ten years ago and still find Fillomino to be a really rich style with a lot of distinct author styles to be found within it.]

Fillomino by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Squeeze Play

Rules: Standard Fillomino rules.

Estimated Difficulty*: 4 stars

Time Standards (highlight to view): Grandmaster = 4:15, Master = 8:30, Expert = 17:00

Solution: PDF; advice on solving this puzzle was also posted in “Ask Dr. Sudoku #10

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Isodoku by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): This snowflake shape was first made for the book Sudoku Masterpieces by me and Wei-Hwa Huang. While the six-linked-cube design is fairly limiting, and some of the region shapes are also quite constrained, the size of the puzzle will take a very observant solver to put all these considerations together and reach the solution.]

Isodoku by Thomas Snyder

PDF

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

Theme: Last snow of winter? This Snowflake Isodoku may not be the last snowflake to fall this winter, but it will be the last snow-based puzzle from us this year.

Rules: Standard Isodoku rules, using numbers 1-8. Some rows connect across the center of the shape by following the gray lines.

Estimated Difficulty*: 4 stars

Time Standards (highlight to view): Grandmaster = 5:15, Master = 9:00, Expert = 18:00

Solution: PDF

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

Fillomino by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): One way to place tension into a Fillomino grid is to have large and small values playing together and potentially competing for space. The repeating values around the central diamond in this Fillomino sets up a lot of the logic for the puzzle’s solution.]

Fillomino by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Rough Diamond, or Diamond in the Rough?

Rules: Standard Fillomino rules.

Estimated Difficulty*: 2.5 stars

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

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Isodoku by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): This second isodoku on the site altered the standard cube shape significantly by flattening out the whole center by looking like a 3 by 3 by 3 cube was removed. The new region shapes now hold some important constraints to make progress in the puzzle.]

Isodoku by Thomas Snyder

PDF

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

Theme: Missing my Rubik’s? This isodoku has 27 fewer “cubes” than Monday’s puzzle.

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

Estimated Difficulty*: 2.5 stars

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

Solution: PDF

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

Fillomino by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): Fillomino is one of our main “region division” puzzle styles, as you try to fit several polyominoes into a grid without similar size regions sharing an edge. In this first Fillomino puzzle on the site from ten years ago, the starting arrangement of 1-8 alongside other two by four groups sets up a beginner’s arrangement of numbers to fit into the grid.]

Fillomino by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Two by Fours

Rules: Standard Fillomino rules.

Estimated Difficulty*: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 1:30, Expert = 3:00

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Isodoku by Thomas Snyder

[This is a repost from our archives with new notes at the top (original post here): This last week of our “first 60” puzzles started with another interesting geometric sudoku variation, that almost looks three-dimensional and changes the meaning of “rows”. While future puzzles would use more altered isodoku shapes, the first puzzle needed to be a standard “cube” with two by four regions.]

Isodoku by Thomas Snyder

PDF

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

Theme: Peace!

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

Estimated Difficulty*: 2 stars

Time Standards (highlight to view): Grandmaster = 1:30, Master = 3:00, Expert = 6:00

Solution: PDF

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

Sunday Update

Our ninth Smashing the Sudoku video including Slitherlink and Deficit/Surplus Sudoku walkthroughs and an update on the Ten-Year Anniversary Contest is now posted:

This coming week will be the last in our look back series on our first 60+1 puzzles and we will then share more details on what is coming up in 2023 for GMPuzzles.