(Note: This bonus puzzle is being posted today to mark the occasion of Prasanna’s birthday.)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a shading mode, a line-drawing mode with diagonal and straight options, and an edge marking mode to add x’s as needed.)

Theme: One Away from Thirty

Author/Opus: This is the 180th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Locate two snakes in the grid. Each snake must start from one of the gray circles, but has an unknown ending point. Black circles represent an interior cell of one of the snakes, and all black circles must be part of a snake. Each snake’s path is allowed to move vertically, horizontally, or diagonally between cells. An interior snake cell can only be adjacent to two other snake cells (including diagonally adjacent cells) and an end of the snake can only be adjacent to one other snake cell (including diagonally adjacent cells). The two different snakes must not share any adjacent cells.

There are some numbers outside the grid. These numbers indicate the number of vertical or horizontal edges (not corners) that snakes cross in that direction.

There are some letters inside the grid. For each distinct letter, exactly one of its instances is visited by one of the two snakes.

Also see this example:

Solution: PDF

(view directly for a larger image)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab key to alternate between loop drawing and letter entry modes)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 277th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Place each of the given words into the grid, reading across or down; all words should interconnect, and all words formed in the grid must be from the list. Each given letter must be used by at least one word. Additionally, draw a Masyu loop: a single closed loop passing through each of the “O”s and otherwise using only unused squares. When passing through an “O”, the loop must go straight through and must make a 90 degree turn in at least one of the adjacent squares.

See also this example:

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 = 7:00, Master = 10:45, Expert = 21:30

Solution: PDF

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

(view directly for a larger image)

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: Down the Middle

Author/Opus: This is the 161st puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Masyu 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 = 3:15, Master = 4:45, Expert = 9:30

Solution: PDF

Note: Follow this link for other classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

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: Logical

Author/Opus: This is the 6th puzzle from guest contributor Freddie Hand.

Rules: Standard Masyu rules, but any two consecutive line segments cannot have the same length (i.e., on both sides of any turn, the loop must travel different lengths).

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 = 3:30, Master = 4:30, Expert = 9:00

Solution: PDF

Note: Follow this link for other Masyu variations and this link for classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

PDF

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

Theme: Antisymmetry

Author/Opus: This is the 3rd puzzle from guest contributor Fatih Kamer Anda.

Rules: Standard Masyu rules, combined with standard Slitherlink 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 = 4:00, Expert = 8:00

Solution: PDF

Note: Follow this link for other Masyu variations and this link for classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

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: Monochrome Borderless

Author/Opus: This is the 17th puzzle from guest contributor Joseph Howard.

Rules: Standard Masyu 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

Solution: PDF

Note: Follow this link for other classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

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: Logical

Author/Opus: This is the 318th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Masyu 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 = 0:30, Master = 0:40, Expert = 1:20

Solution: PDF

Note: Follow this link for other classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between edgex mode where left click+drag draws lines and right click marks X’s and a shading mode)

Theme: S for Slitherlink

Author/Opus: This is the 5th puzzle from guest contributor Freddie Hand.

Rules: Variation of Slitherlink rules. Draw a set of eleven pentomino-shaped loops (i.e., all but one of the given shapes) consisting of vertical and horizontal segments between the dots. Numbers inside a cell indicate how many of the edges of that cell are part of the loops. The pentomino-shaped loops cannot be in adjacent cells that share an edge or corner, and may be rotated or reflected.

See also this example:

Answer String: For each marked row, enter the length in cells of each connected group inside the loops from left to right. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 8:00, Master = 10:30, Expert = 21:00

Solution: PDF

Note: Follow this link for other Slitherlink variations and this link for classic Slitherlink. If you are new to this puzzle type, here are our easiest Slitherlink puzzles to get started on. More Slitherlink puzzles can be found in The Art of Puzzles, Slitherlink and Variations, and our beginner-friendly book Logic Puzzles 101.

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: Logical

Author/Opus: This is the 316th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Masyu 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 = 0:35, Master = 0:45, Expert = 1:30

Solution: PDF

Note: Follow this link for other classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.

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: Antisymmetry

Author/Opus: This is the 36th puzzle from our contributing puzzlemaster Ashish Kumar.

Rules: Standard Masyu 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 = 0:40, Master = 1:00, Expert = 2:00

Solution: PDF

Note: Follow this link for other classic Masyu. If you are new to this puzzle type, here are our easiest Masyu to get started on. More Masyu puzzles can be found in The Art of Puzzles and in our beginner-friendly book Logic Puzzles 101.