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

Theme: Nothing in the Middle

Author/Opus: This is the 1st puzzle from guest contributor Akash Doulani.

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 3rd row from left to right, followed by a comma, followed by the 6th row from left to right.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:45, Expert = 9:30

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.

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.

Theme: Clueless

Author/Opus: This is the 343rd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Thermo-Sudoku rules.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 6th row from left to right.

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

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

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.

Theme: 2×2 Center

Author/Opus: This is the 20th puzzle from guest contributor Ashish Kumar.

Rules: Standard Castle Wall rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

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

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 146th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Castle Wall rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 7:30, Expert = 15:00

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Windmill

Author/Opus: This is the 19th puzzle from guest contributor Ashish Kumar.

Rules: Standard Castle Wall rules, but none of the clue colors are given. For each symmetric pair of clue cells (reflecting through the center of the grid), one cell is white and the other cell is black.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 4:45, Master = 6:30, Expert = 13:00

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 268th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Castle Wall. Clue cell colors have the usual meaning. However, the numbers cannot be correct clues for any of the four directions (left, right, up, down) around the cell.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 5:15, Expert = 10:30

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: XO

Author/Opus: This is the 267th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Castle Wall rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:15, Expert = 6:30

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 18th puzzle from guest contributor Ashish Kumar.

Rules: Classic Castle Wall rules. Also, the loop must go straight through the cells with white circles, with a turn in at least one of the cells immediately before/after each white circle. The loop must make a turn in all the black circles, but must go straight in both cells immediately before/after each black circle.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 2:00, Master = 2:45, Expert = 5:30

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Only 1 Antisymmetry

Author/Opus: This is the 4th puzzle from guest contributor İlay Zehra Şenay.

Rules: Standard Castle Wall rules.

Answer String: Enter the length in cells of the vertical loop segments from top to bottom in the marked columns, starting at the left. If the loop only has horizontal segments in the marked column, enter 0. Separate each column’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 1:11, Master = 1:40, Expert = 3:20

Solution: PDF

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.

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.

Theme: Yin Yang

Author/Opus: This is the 266th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Castle Wall rules.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:00, Expert = 4:00

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.