(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Three more numbers (13, 14, 15) are here in this Advent Calendar edition of XV Pairs Sudoku.

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or solve online (using SudokuPad)

Author/Opus: This is the 67th 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). Whenever an X or V, reflecting the Roman numerals for 10 or 5, is placed on the edge between cells, the numbers in the two adjacent cells must sum to exactly 10 or 5. (Pairs of cells without an X or V mark can have any sum value. Also, the cages surrounding some givens are just showing part of the visual theme and have no other meaning.)

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00. All other solvers earn a 🦕: Dawdling Domeykosaurus.

Thomas Hits the GAS (highlight to view): 4:09, 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 less common variations of Sudoku.

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.)
The short palindrome sequences in this puzzle lead to some amazing deductions. Can you figure this GAS puzzle out?

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or solve online (using SudokuPad)

Theme: Spike Island

Author/Opus: This is the 64th puzzle from Bill Murphy, 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). The numbers along each gray line form a palindrome (i.e., read the same forwards and backwards).

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

Thomas Hits the GAS (highlight to view): 2:28, 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 less common variations of Sudoku.

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.)
In this “Two-Variant Tango”, Arrow and Consecutive Pairs clues are working closely together to set up a fun logical dance.

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Theme: Two-Variant Tango

Author/Opus: This is the 85th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Arrow Sudoku rules: Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Some arrow shapes are in the grid; the sum of the numbers along the path of each arrow must equal the number in the circled cell. Numbers can repeat within an arrow shape. Also, if a white circle is given between two adjacent cells, then the two numbers in those cells must differ by 1. Pairs of cells without circles can have any relationship.

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

Thomas Hits the GAS (highlight to view): 2:05, 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 Arrow Sudoku. Follow this link for Consecutive Pairs Sudoku puzzles on this website. If you are new to these puzzle types, here are our easiest Arrow Sudoku and easiest Consecutive Pairs Sudoku to get started on. More Arrow Sudoku puzzles can be found in these books in our e-store and more Consecutive Pairs Sudoku puzzles can be found in these books.

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.)
The advent calendar continues with this Killer Sudoku with three 4-cell regions matching to 10, 11, and 12. Can you figure out their special logic to make progress?

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or solve online (using SudokuPad)
or try the harder givenless version that Thomas solved (using SudokuPad)

Theme: Nerf Me, Baby, One More Time

Author/Opus: This is the 66th 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, the sum of the numbers in each cage must equal the value given in the upper-left corner of that cage. Numbers cannot repeat inside a cage.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 7:30; One party hat (🥳): 15:00. All other solvers earn a 🦕: Antiquated Abdallahsaurus.

Thomas Hits the GAS (highlight to view): 3:18 on the givenless version, 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 Killer Sudoku and this link for classic Sudoku. More Killer Sudoku puzzles can be found in Killer Sudoku by Serkan Yürekli.

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.)
This puzzle adds four more regions and that must make it extra hardcore (or at least really special for GAS).

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or solve online (using SudokuPad)

Author/Opus: This is the 63rd puzzle from Bill Murphy, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. The shaded regions must also contain 1 to 9 without repeats.

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

Thomas Hits the GAS (highlight to view): 2:27, 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 less common variations of Sudoku.

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.)
Today’s GAS features the full Battenburg dessert: the checkerboard clues show where an alternating even/odd pattern must appear and the absence of such clues indicates there is no such “pretty” pattern in that space.

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or solve online (using SudokuPad)

Theme: Accentuate the Negative

Author/Opus: This is the 84th 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). Whenever a checkerboard clue appears at the intersection of four cells, the numbers in those cells must form a “checkerboard” pattern of odd and even (i.e., one diagonally opposite pair is odd and the other pair is even). All possible checkerboard clues have been given, so any sets of four cells without a clue cannot have a “checkerboard” pattern of odd and even.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00. All other solvers earn a 🦕: negative Neovenator.

Thomas Hits the GAS (highlight to view): 2:54, 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 less common variations of Sudoku.

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.)
An advent calendar helps us count consecutive days until Christmas, like the 789 here in Philip’s GAS for today.

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or solve online (using SudokuPad)

Theme: Eight Nine, Seven Did

Author/Opus: This is the 65th 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). Numbers along each line must form a non-repeating consecutive set, in any order. (For example, a 4-cell Renban line could be 4352, but not 5679 or 2312. Also, the cages surrounding some givens are just showing part of the visual theme and have no other meaning.)

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

Thomas Hits the GAS (highlight to view): 2:56, 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 less common variations of Sudoku.

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.)
This puzzle might be just average — if you look at the numbers in the circled cells at least. Each arrow describes the average value along its length.

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or solve online (using SudokuPad)

Author/Opus: This is the 62nd puzzle from Bill Murphy, 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). Some arrow shapes are in the grid; the number in the circled cell is equal to the average of all numbers along the arrow. (For example, as R2C3 = 2, the average of R2C4 and R2C5 is 2.)

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

Thomas Hits the GAS (highlight to view): 2:08, 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 less common variations of Sudoku.

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.)
Today’s GAS features the good part of Checkerboard (parity) logic and not the potentially hidden side that can be trickier.

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or solve online (using SudokuPad)

Theme: Accentuate the Positive

Author/Opus: This is the 83rd 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). Whenever a checkerboard clue appears at the intersection of four cells, the numbers in those cells must form a “checkerboard” pattern of odd and even (i.e., one diagonally opposite pair is odd and the other pair is even). Sets of cells without such a clue can have any arrangement of numbers and parities.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00. All other solvers earn a 🦕: positive Poekilopleuron.

Thomas Hits the GAS (highlight to view): 3:19, 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 less common variations of Sudoku.

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.)
The advent positions are the same but this gift tag looks like a quite different puzzle than the classic Sudoku from the 3rd. Is this gift going to be for you?

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or solve online (using SudokuPad)

Theme: Giften Tag

Author/Opus: This is the 64th 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). Numbers in cells directly connected on a green line must differ by at least 5. (The cages surrounding some givens are just showing part of the visual theme and have no other meaning.)

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00. All other solvers earn a 🦕: Laurasian Long-Neck.

Thomas Hits the GAS (highlight to view): 4:26, 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 less common variations of Sudoku.

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.