(view directly for a larger image)

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: Logical

Author/Opus: This is the 3rd puzzle from guest contributor Yuki Kawabe.

Rules: Combination of Sundoko, Snake, and Shape puzzle styles.

Sundoko: Shade some cells to make sunglasses, consisting of a bridge (a given line, in red) and two lenses made out of orthogonally connected cells that are symmetric with respect to the perpendicular bisector of the bridge. Two lenses may not share an edge, but can intersect at a point. Cells with the bridges are not shaded, except at the bridge ends. Numbers in the grid are unshaded, and indicate the total count of unshaded cells connected vertically and horizontally to the numbered cell, including the cell itself.
Sundoko example:

Snake: Shade some cells to create a one-cell wide snake in the grid that does not cross or touch itself, not even diagonally. The snake starts and ends at the black circles and must pass through all white circles.
Snake example:

Shape: Place each of the given shapes into the grid exactly once (rotations and reflections allowed). Shapes cannot touch each other, not even diagonally.
Shape example:

SSS: In SSS, shade some cells to make sunglasses, create a single snake, and place all of the shapes in the grid. Shaded cells of different categories (sunglasses, snake, shapes) cannot share an edge. Number clues referring to unshaded cell counts consider all three categories of objects as shaded cells in this hybrid.

Or see this example:

Answer String: Enter the length in cells of each of the shaded segments (sunglasses, snake, and shapes) 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 = 16:00, Master = 22:00, Expert = 44:00

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

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: Logical

Author/Opus: This is the 2nd puzzle from guest contributor Yuki Kawabe.

Rules: Combination of Sundoko, Snake, and Shape puzzle styles.

Sundoko: Shade some cells to make sunglasses, consisting of a bridge (a given line, in red) and two lenses made out of orthogonally connected cells that are symmetric with respect to the perpendicular bisector of the bridge. Two lenses may not share an edge, but can intersect at a point. Cells with the bridges are not shaded, except at the bridge ends. Numbers in the grid are unshaded, and indicate the total count of unshaded cells connected vertically and horizontally to the numbered cell, including the cell itself.
Sundoko example:

Snake: Shade some cells to create a one-cell wide snake in the grid that does not cross or touch itself, not even diagonally. The snake starts and ends at the black circles and must pass through all white circles.
Snake example:

Shape: Place each of the given shapes into the grid exactly once (rotations and reflections allowed). Shapes cannot touch each other, not even diagonally.
Shape example:

SSS: In SSS, shade some cells to make sunglasses, create a single snake, and place all of the shapes in the grid. Shaded cells of different categories (sunglasses, snake, shapes) cannot share an edge. Number clues referring to unshaded cell counts consider all three categories of objects as shaded cells in this hybrid.

Or see this example:

Answer String: Enter the length in cells of each of the shaded segments (sunglasses, snake, and shapes) 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 = 3:45, Master = 5:15, Expert = 10:30

Solution: PDF

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 47th puzzle from our contributing puzzlemaster Palmer Mebane.

Rules: Shade some empty cells black to create a single connected wall (the “Coral”). The shaded cells cannot form a 2×2 square anywhere in the grid, and all unshaded cells including clue cells must be connected to an edge of the grid. Clues in the gray cells indicate the lengths of the first shaded segments visible from this cell in all four directions (clues are given in ascending order). [For clarity, when considering the “first shaded segment” in a direction, gray cells see through all empty and gray cells to the edge of the grid when finding this segment, if any.]

Also see this example:

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 = 4:30, Master = 8:00, Expert = 16:00

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

Editorial Note: Many solvers can confuse Coral with another puzzle type with similar spelling. An easy way to remember the difference is that Cave has no R’s and also has no 2×2 Region constraint. Coral puzzles, with an R, do have this region constraint. The other general rules (about not enclosing white spaces and having a single shaded group) are shared between Cave and Coral puzzles.

(Note: this puzzle is like a Sunday Surprise with very high difficulty.)

(view directly for a larger image)

PDF

Theme: 14 Nisan, 2018 (Pasch 5778)

Author/Opus: This is the 45th puzzle from our contributing puzzlemaster John Bulten.

Rules: See PDF link above for complete rules as well as a solvable example by Thomas Snyder.

Answer String: The solution string is 3 words in ABC order, in all capital letters and separated by commas. (There are a total of 28 letters in this string.)

Time Standards (highlight to view): No time standard (GM time > 2hr).

Solution: Answers for this week in this PDF.

Editor’s Note: The giant grid here is one of the hardest puzzles we have ever presented. If I knew in advance John wanted to make a puzzle like this, I would have said no because of the combination of so many kinds of rules, new puzzle styles, and my expectation it would take hours to solve (and it certainly does!). But there is something inspirational about the elements brought together here by John, many unexpected Ahas that will cure the headaches you’ll also get in the middle. While the giant puzzle was originally created to stand on its own, John added the four medium difficulty puzzles we posted earlier this week to introduce the four subgenres. Be sure to solve these as you prepare for this large test at the end of the week. -TS

Author’s Note: Thanks to Thomas and Grant for encouraging me to construct new puzzle types. Thanks to patron Randy Rogers for requesting 4-grid combination puzzles, which sparked this idea. Thanks to Prasanna for his giant 11/29/15, 3/2/16, and 3/2/17 puzzles, which directly inspired this puzzle. Thanks to Serkan for inventing Light and Shadow, because whenever I tried experimenting with shading puzzles I found myself trying to reinvent Light and Shadow. Thanks to Izak for inventing Surf, which has more potential than either of us realize. Thanks to God for this day. -JB

(Note: puzzles during this bonus week are harder than usual; the four puzzles from Monday-Thursday are all about Thursday or Friday level difficulty.)

PDF

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

Theme: Maze

Author/Opus: This is the 44th puzzle from our contributing puzzlemaster John Bulten.

Rules: Shade some white cells black so that exactly one of the grid’s clues appears in each contiguous white or black region and indicates the clued region’s area. Circled numbers indicate cells that must remain white.

Also see this example:

Answer String: Enter the length in cells of each of the black segments 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 = 4:30, Master = 7:45, Expert = 15:30

Solution: Answers for this week in this PDF.

Note: Light is John Bulten’s variation of the shading puzzle Light and Shadow, created by Serkan Yürekli. Unlike Light and Shadow, where all numbered cells start white or black, in Light puzzles the numbered cells that are not shaded or circled may be either white or black in the solution.

(Note: puzzles during this bonus week are harder than usual; the four puzzles from Monday-Thursday are all about Thursday or Friday level difficulty.)

PDF

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

Theme: Hidden

Author/Opus: This is the 43rd puzzle from our contributing puzzlemaster John Bulten.

Rules: Shade some white cells black so that each contiguous white region is a valid Four Winds region (that is, the white region consists of at least two white cells, and has at most one “central” cell where both vertical and horizontal connections are made; if the white region contains a numeric clue, this clue must be the “central” cell and represent the count of all other cells in the region, which must be connected vertically or horizontally to this clue). An arrow clue must belong to a white region and point to its “central” cell (assignment of which cell is “central” is not necessary in one-cell-wide rectangular regions). The contiguous black regions can contain zero, one, or more clues. All clues inside a black region must indicate that region’s area.

Also see this example:

Answer String: Enter the length in cells of each of the black segments 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 = 4:45, Master = 8:00, Expert = 16:00

Solution: Answers for this week in this PDF.

Note: Winddraughts is John Bulten’s variation on the puzzles Four Winds and Checkered Fillomino.

(Note: puzzles during this bonus week are harder than usual; the four puzzles from Monday-Thursday are all about Thursday or Friday level difficulty.)

PDF

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

Theme: Anchor

Author/Opus: This is the 42nd puzzle from our contributing puzzlemaster John Bulten.

Rules: Shade some white cells black so that one of the grid’s clues in each contiguous white or black region indicates the clued region’s area. (Each contiguous region must therefore have at least one clue.) Any other clue in the region must indicate how many of the clued cell’s immediate neighbors are white (up to 9, including itself).

Also see this example:

Answer String: Enter the length in cells of each of the black segments 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 = 3:45, Master = 6:15, Expert = 12:30

Solution: Answers for this week in this PDF.

Note: Turf is a shading puzzle created by John Bulten. We will have several more Turf puzzles from John in a few months when we start a new “Puzzlemasters’ Workshop” book series.

(Note: puzzles during this bonus week are harder than usual; the four puzzles from Monday-Thursday are all about Thursday or Friday level difficulty.)

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: Pi

Author/Opus: This is the 41st puzzle from our contributing puzzlemaster John Bulten.

Rules: Shade some white cells black so that the grid is divided into white and black regions. Cells with numbers cannot be shaded. Each white region must contain exactly one number and have the same area in cells as that number. Two white or two black regions may only touch diagonally. Each black region must be exactly specified by one shape graph given below the grid, where graph edges represent one-cell-wide straight paths with variable lengths, and graph nodes represent ends, turns, and branch points. Graphs can be rotated and reflected, and, if multiple graphs are given, not all need be used.

Also see this example:

Answer String: Enter the length in cells of each of the black segments 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 = 3:45, Master = 6:00, Expert = 12:00

Solution: Answers for this week in this PDF.

Note: Surf is a shading/object placement puzzle created by Izak Bulten, which draws on elements from other shading puzzles like Nurikabe. We will have several more Surf puzzles from Izak and John Bulten in a few months when we start a new “Puzzlemasters’ Workshop” book series.

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

(View image directly for larger form.)

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: 27 years from 03-02-1991 to 03-02-2018

Author/Opus: This is the 160th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: (This puzzle uses standard “Canal View” rules.) Shade some empty cells black to create a single connected group. Cells with numbers cannot be shaded, and the shaded cells cannot form a 2×2 square anywhere in the grid. Each numbered cell indicates the total count of shaded cells connected vertically and horizontally to that numbered cell.

Also, in addition to standard Canal View rules, the clues outside the grid on the top and left indicate the difference in lengths of the largest and smallest shaded groups in that row/column (the smallest group must be >0 cells in size and there must be at least two groups in that row/column). The clues outside the grid on the bottom and right indicate the number of shaded groups in that row/column. All ? clues must stand for prime numbers (2, 3, 5, 7, …).

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 = 10:00, Master = 22:00, Expert = 44:00

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).

Theme: X’s and O’s (for Jamie Hargrove)

Author/Opus: This is the 291st puzzle from Thomas Snyder, aka Dr. Sudoku.

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 = 2:30, Master = 4:30, Expert = 9:00

Solution: PDF

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