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: Anti-symmetry

Author/Opus: This is the 140th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Draw a single closed loop that passes vertically and horizontally through all cells. The loop must go through all of the given dots. When passing through a white dot, the number of cells on one side of the dot before turning must differ by 1 from the number of cells on the other side before turning. When passing through a black dot, the number of cells on one side of the dot before turning must be twice the number of cells on the other side before turning. (Not all possible dots are given; if a line crosses two dots, ignore the other dot and count cells as if it is not there.)

Also, see 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 = 4:00, Master = 5:45, Expert = 11:30

Solution: PDF

Note: Follow this link for other less common Loop variations.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 139th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Battleships rules. Also, the arrows point at the closest ship segment(s) from that cell. No ship segment can be placed in a cell with an arrow.

Answer String: For each row from top to bottom, enter the number of the first column from the left where a ship segment appears (enter both digits if a two-digit number). If the row is empty, enter 0. Enter these numbers as a single string with no separators.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:00, Expert = 8:00

Solution: PDF

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

PDF

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

Theme: Logical

Author/Opus: This is the 138th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of Nurikabe. Shade some of the numbered cells so that the grid is divided into white regions, with each cell in such a region containing a number identical to the area of the region. Two white regions may only touch diagonally. All shaded cells must be connected with each other, but no 2×2 group of cells can be entirely shaded black.

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:30, Expert = 7:00

Solution: PDF

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

PDF

or solve online (using our beta test of Penpa-Edit tools. Use left click to place mine, right click (in cell) to mark unused, right click (on edge/corner) to mark a note; hitting tab will also enable a shading mode. If you want more solving options, turn off Penpa-Lite option.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 139th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Place a mine into some of the empty cells so that each number represents the total count of mines in neighboring cells, including diagonally adjacent cells. Also, an even number of mines must be placed in each row and in each column.

Answer String: Enter the length in cells of each group of consecutive cells with mines from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

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

Solution: PDF; a solution video is available here.

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 137th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Nanro rules. Also, an even number of cells must be filled with a number in each row and in each column.

Answer String: Enter the length in cells of each of the segments labeled with numbers from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 7:30, Master = 9:30, Expert = 19:00

Solution: PDF

Note: Follow this link for other Nanro variations and this link for classic Nanro. If you are new to this puzzle type, please first try out our easiest Nanro to get started.

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 50th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Yajilin rules. Also, an even number of cells must be blackened in each row and in each column.

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 other variations of Yajilin and this link for classic Yajilin. If you are new to this puzzle type, here are our easiest Yajilin to get started on.

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 49th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Cave rules. Also, an even number of cells in each row and in each column must be inside the cave.

Answer String: Enter the length in cells of each of the cave segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 6:30, Expert = 13:00

Solution: PDF

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

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: Clue Symmetry and Logic

Author/Opus: This is the 138th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Slitherlink rules. Also, an even number of cells in each row and in each column must be inside the loop.

Answer String: Enter the length in cells of each of the internal loop segments following the arrows for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 6:15, Expert = 12:30

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.

PDF

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

Theme: Logical

Author/Opus: This is the 223rd puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Cross the Streams rules. Also, an even number of cells must be shaded in each row and in each column.

Answer String: Enter the length in cells of each of the black segments from top to bottom for the marked columns, going in order from A to B to C to D and separating each entry with a comma.

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

Solution: PDF

Note: Follow this link for variations of Cross the Streams and this link for other classic Cross the Streams. If you are new to this puzzle type, here are our easiest Cross the Streams to get started on.

PDF

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

Theme: Five (appeared in the 2016 Puzzle Grand Prix playoffs)

Author/Opus: This is the 255th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Variation of Nanro.

Label some cells with numbers to form a single connected group of labeled cells. No 2×2 group of cells may be fully labeled. Each number must be equal to the total count of labeled cells in that bold region, and all bold regions contain at least one labeled cell. The given numbers indicate how many cells are labeled in that region (but not necessarily which cells are labeled). When two numbers are orthogonally adjacent across a region boundary, the numbers must be different.

Also see this example:

Answer String: Enter the length in cells of each of the segments labeled with numbers from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 6:15, Expert = 12:30

Solution: PDF

Note: Follow this link for Nanro puzzles on this website and this link for variations on Nanro puzzles. If you are new to this puzzle type, here are our easiest Nanro Puzzles to get started on. More Nanro puzzles can be found in A Number o’ Nanro by Prasanna Seshadri.