PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a shading mode.)

Theme: Logical

Author/Opus: This is the 3rd puzzle from guest contributor Dan Katz.

Rules: Standard Spiral Galaxies rules.

[Copying the rules here as this is the first week: Divide the grid along the indicated lines into connected regions – “galaxies” – with rotational symmetry. Each cell must belong to one galaxy, and each galaxy must have exactly one circle at its center of rotational symmetry.]

Answer String: Enter the number of cells in each connected group (between bold lines) in the marked rows. Separate each row’s entry from the next with a comma. The example has the answer “2131,331”.

Time Standards (highlight to view): Grandmaster = 1:20, Master = 2:30, Expert = 5:00

Solution: PDF

Note: Follow this link for classic Spiral Galaxies puzzles on this website and this link for variations on Spiral Galaxies puzzles. If you are new to this puzzle type, here are our easiest Spiral Galaxies Puzzles to get started on. More Spiral Galaxies puzzles will soon be found in The Art of Puzzles 2.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a shading mode.)

Theme: Happy Face

Author/Opus: This is the 280th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Spiral Galaxies rules.

[Copying the rules here as this is the first week: Divide the grid along the indicated lines into connected regions – “galaxies” – with rotational symmetry. Each cell must belong to one galaxy, and each galaxy must have exactly one circle at its center of rotational symmetry.]

Answer String: Enter the number of cells in each connected group (between bold lines) in the marked rows. Separate each row’s entry from the next with a comma. The example has the answer “2131,331”.

Time Standards (highlight to view): Grandmaster = 1:30, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for classic Spiral Galaxies puzzles on this website and this link for variations on Spiral Galaxies puzzles. If you are new to this puzzle type, here are our easiest Spiral Galaxies Puzzles to get started on. More Spiral Galaxies puzzles will soon be found in The Art of Puzzles 2.

PDF

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

Theme: Clue Symmetry & Logic

Author/Opus: This is the 6th puzzle from guest contributor Jamie Hargrove.

Rules: Place each of the twelve pentominoes into the grid once, with rotations and reflections allowed. No two pentominoes can overlap or be orthogonally adjacent, and all cells not occupied by the pentominoes must be orthogonally connected. The black circles indicate some cells that must be covered by pentominoes. Some numbers and arrows are also given in the grid. For all numbers that are not covered by a pentomino, the clues give the exact count of shaded cells in the given direction. A shaded over clue may or may not be true.

Answer String: Enter the length in cells of each of the shaded segments 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 = 17:15, Expert = 34:30

Solution: PDF

Note: Follow this link for other Statue Park Puzzles and this link for other less common Shading puzzles including Yajisan Kazusan puzzles.

PDF

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

Theme: No 2×2 White Blocks

Author/Opus: This is the 5th puzzle from guest contributor Jamie Hargrove.

Rules: Shade some cells black so that all unshaded number and arrow clues indicate the exact count of shaded cells in the given direction. Shaded cells cannot share an edge, and all white cells must remain connected as part of a single contiguous group. It is allowed to shade over some of the numbered cells; a shaded over clue may or may not be true. Also, as an extra rule from standard Yajisan Kazusan, there cannot be any fully unshaded 2×2 cell blocks in the grid.

Answer String: For each row from top to bottom, enter the number of shaded cells as a single string.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 12:00, Expert = 24:00

Solution: PDF

Note: Follow this link for other less common Shading puzzles.

PDF

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

Theme: Clue Symmetry & Logic

Author/Opus: This is the 4th puzzle from guest contributor Jamie Hargrove.

Rules: Variation of Nurikabe. Some of the given island clues are actually part of the ocean and must be shaded over. (All other Nurikabe rules still apply, including all islands contain exactly one clue number equal to the area of the island.)

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. Enter both digits for any two-digit number. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 8:15, Expert = 16:30

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

Note: Follow this link for other classic Nurikabe. If you are new to this puzzle type, here are our easiest Nurikabes to get started on.

PDF

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

Theme: 2×2 Clue Blocks

Author/Opus: This is the 3rd puzzle from guest contributor Jamie Hargrove.

Rules: Shade some cells black so that all unshaded number and arrow clues indicate the exact count of shaded cells in the given direction. Shaded cells cannot share an edge, and all white cells must remain connected as part of a single contiguous group. It is allowed to shade over some of the numbered cells; a shaded over clue may or may not be true.

Also, see this example:

Answer String: For each row from top to bottom, enter the number of shaded cells as a single string. For the example, the answer is “20212”.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 5:15, Expert = 10:30

Solution: PDF

Note: Follow this link for other less common Shading puzzles.

(view directly for a larger image)

PDF

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

Theme: Open Seas

Author/Opus: This is the 2nd puzzle from guest contributor Jamie Hargrove.

Rules: Standard Nurikabe rules.

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. Enter both digits for any two-digit number. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 5:15, Master = 11:30, Expert = 23:00

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)

Theme: Logical

Author/Opus: This is the 1st puzzle from guest contributor Jamie Hargrove.

Rules: Standard Nurikabe rules.

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. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 4:15, Expert = 8:30

Solution: PDF

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

(View image directly for larger form.)

PDF

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

Theme: Ladders

Author/Opus: This is the 1st puzzle from guest contributor David Olmsted.

Rules: Standard Yajilin 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 = 7:30, Master = 13:45, Expert = 27:30

Solution: PDF

Note: Follow this link for other classic Yajilin. If you are new to this puzzle type, here are our easiest Yajilin to get started on. More Yajilin puzzles can be found in The Art of Puzzles 2.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Clue Symmetry & Logic

Author/Opus: This is the 1st puzzle from guest contributor Takeya Saikachi.

Rules: Divide the grid along the boundary lines so that every cell belongs to a snake. A snake is a one-cell-wide path at least two cells long that does not touch itself, not even diagonally. Circled cells must be at one of the ends of a snake. A snake may contain one circled cell, two circled cells, or no circled cells at all. Numbered cells must be part of a snake with a length of exactly that number of cells. A snake may contain one number, multiple identical numbers, or no numbers at all. Two snakes of the same length cannot touch each other horizontally or vertically. [+ new rule] Cells with an X cannot be an end of a snake.

Also see this example:

Answer String: For each cell in the marked rows/columns, enter the length of the snake it belongs to. Enter just the last digit for any two-digit number. This example has the key “33553,44664”.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 10:30, Expert = 21:00

Solution: PDF

Note: Follow these link for other Fillomino or Snake puzzles.