(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
What are the odds?? Today’s puzzle is an Odd Sudoku, and it’s an oddity for GAS, being trickier than most. Keep in mind how many odds and evens you need in each row, column, and region.

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Theme: An Odd Coincidence

Author/Opus: This is the 89th puzzle from Philip Newman, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 9:59; One party hat (🥳): 19:59. All other solvers earn a 🦕: Futuristic Futalognkosaurus.

Thomas Hits the GAS (highlight to view): 6:13, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF; solving video with explanation to be added later from GAS team.

Note: Follow this link for other 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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Put on your eveningwear and get ready for a date (of the calendar variety) with today’s Valentine’s Eve puzzle, an Even/Odd Sudoku. Eventually, the GAS team might even include both Even and Odd clues in the same puzzle.

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Theme: Valentine’s, Even

Author/Opus: This is the 87th puzzle from Philip Newman, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:00; One party hat (🥳): 14:00. All other solvers earn a 🦕: Darling Daanosaurus.

Thomas Hits the GAS (highlight to view): 2:35, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other 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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Here is a rather even Even/Odd Sudoku from clover!; if you examine the clue cells carefully you might catch onto why.

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Theme: Granny Squares

Author/Opus: This is the 95th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:30; One party hat (🥳): 12:00. All other solvers earn a 🦕: quilting Kazaklambia.

Thomas Hits the GAS (highlight to view): 1:40, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Here is a rather odd Even/Odd Sudoku from clover!; if you examine the clue cells carefully you might catch onto why.

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or solve online (using SudokuPad)

Theme: Sierpinski

Author/Opus: This is the 94th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:30; One party hat (🥳): 12:00. All other solvers earn a 🦕: carpeted Camelotia.

Thomas Hits the GAS (highlight to view): 1:49, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Here comes a familiar variant from Clover with even squares and odd circles giving the parity of some of the cells along the solving path.

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or solve online (using SudokuPad)

Author/Opus: This is the 59th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 7:00; One party hat (🥳): 13:00. All other solvers earn a 🦕: alternating Angaturama.

Thomas Hits the GAS (highlight to view): 2:03, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Philip returns with this familiar pattern, and a very difficult set of placements with only a few parity clues shared in the form of even squares and odd circles to break through.

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Theme: I Won’t Back Down

Author/Opus: This is the 39th puzzle from Philip Newman, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cells with a square contain an even number; cells with a circle contain an odd number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 10:00; One party hat (🥳): 25:00. All other solvers earn a 🦕: Partitioned Protognathus.

Thomas Hits the GAS (highlight to view): 6:07, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is a free “warm-up” puzzle; Season 4 subscribers will see today’s main puzzle in the same style posted at 9:05 AM PT.

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Theme: Four i’s

Author/Opus: This is the 53rd puzzle from our contributing puzzlemaster Takeya Saikachi.

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

Estimated Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:15, Expert = 2:30

Solution: PDF and solving animation.

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 can be found in these books in our e-store.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Week 10 Discussion post on the GMPuzzles Discord.

[This puzzle comes from the 2022 US Sudoku Grand Prix round. The majority of the sudoku variants had visual “eight” themes as well as interesting logical paths. This Even/Odd Sudoku uses a symmetrical set of even/odd cells in only a few rows and columns in an “eight” shape to highly constrain the grid. I deliberately tried to avoid giving any eights on the outside frame of the grid.]

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

Theme: Big Eight

Author/Opus: This is the 438th 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).

Estimated Difficulty: 3 stars

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 and Masterpiece Sudoku Mix 1.

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

Theme: Diagonal Bridge

Author/Opus: This is the 15th puzzle from guest contributor Swaroop Guggilam.

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

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 5:45, Master = 9:30, Expert = 19:00

Solution: PDF and solving video.

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 and Masterpiece Sudoku Mix 1.

PDF

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

Theme: Percentage

Author/Opus: This is the 228th puzzle from our contributing puzzlemaster Prasanna Seshadri.

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

Difficulty: 3 stars

Time Standards (highlight to view): Grandmaster = 3:45, Master = 5:45, Expert = 11:30

Solution: PDF; a solution video is also available here.

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 and Masterpiece Sudoku Mix 1.