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.

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.

PDF

or solve online (using our beta test of Penpa-Edit tools using a composite mode where left click inside cell shades square, left click + drag draws line segment, right click inside cell adds dot, and right click on cell edge adds an x.)

Theme: One Letter Clue

Author/Opus: This is the 3rd puzzle from guest contributor Nikolai Beluhov.

Rules: Draw a snake (a 1 cell-wide path) in the grid whose head and tail are given by circled cells. The snake can touch itself diagonally, but cannot touch itself orthogonally. All cells that are not part of the snake must be part of a pentomino (i.e., an orthogonally connected group of five cells). These unused pentominoes cannot touch orthogonally but can touch diagonally. A letter in a cell represents the pentomino shape that the cell belongs to. Pentomino shapes can be repeated in the grid, and can also be rotated and reflected. (Lettered cells cannot be used by the snake.)

Answer String: Enter the number of cells in each of the snake 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 = 4:45, Master = 7:15, Expert = 14:30

Solution: PDF; a solution video is available here.

Note: Follow this link for other Snake puzzles.

PDF

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

Theme: Logical

Author/Opus: This is the 9th puzzle from guest contributor Bryce Herdt.

Rules: [Variation of LITS]. Shade exactly four connected cells in each outlined region, to form an L, O, T, or S tetromino, so that the following conditions are true:
(1) All shaded cells are connected with each other;
(2) No 1×4 group of cells can be entirely shaded black;
(3) When two tetrominoes in adjacent regions share an edge, they must not be of the same type (L, O, T, or S), regardless of rotations or reflections.

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 = 3:30, Master = 5:15, Expert = 10:30

Solution: PDF

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

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a letter entry mode and a shading mode to mark off the clues.)

Theme: Two Lonely Dots (prepared for the 2017 Puzzle Grand Prix)

Author/Opus: This is the 275th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Place all the given strings into the grid, one letter per cell, so they can be read from left to right or from top to bottom, without crossing or overlapping each other. A dot between two cells indicates that both cells must contain the same letter. All possible dots are given.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 7th row from left to right. USE CAPITAL LETTERS. If a cell is empty, use X for that cell.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 13:00, Expert = 26:00 (*Estimates from competition scoring, not our usual process)

Solution: PDF

Note: Follow this link for other word puzzles.

(View image directly for larger form.)

PDF

or solve online (using our beta test of Penpa-Edit tools in yajilin mode where left click shades squares, left click+drag draws lines and right click marks X’s; note that the default puzzle info is too long — even for an url shortener — so copy and paste all the text in this file into the “Load” option in the upper-right of the penpa-edit interface to access.)

Theme: Clue Symmetry and Logic (for TheSubro)

Author/Opus: This is the 158th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: This puzzle combines four loop varieties commonly featured at GMPuzzles: Balance Loop (upper left), Yajilin (upper right), Castle Wall (lower left), and Masyu (lower right).

Draw a single, non-intersecting loop throughout all four quadrants. The loop may enter and exit the different quadrants as many times as needed.

The standard rules for each puzzle type are true for each quadrant, with these additional considerations:

Balance Loop: Use the entire length of segments (including parts of the segments that extend into an adjacent quadrant) when determining the balanced/unbalanced status of a circle clue.

Yajilin: The arrow clues refer only to shaded cells within the Yajilin quadrant. The loop must occupy all cells adjacent to a shaded cell, even in an adjacent quadrant.

Castle Wall: Number clues only apply within the grid and DO NOT include any line segments that cross the bold border with another grid or any segments in other quadrants. (Another way to say this is that the Castle Wall clues refer to the number of thin lines crossed in the lower-left quadrant only.)

Masyu: Normal rules apply for white and black circles, but the path satisfying these rules can extend into an adjacent quadrant. (For example, a white circle can be passed through crossing a quadrant edge, provided it turns immediately on one side of the circle whether the turn is in the Masyu quadrant or in another quadrant.)

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.

Solution: PDF

Time Standards (highlight to view): Grandmaster = 18:00, Master = 35:00, Expert = 1:10:00

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 (for Chris Green)

Author/Opus: This is the 157th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Castle Wall rules. Also, the grid is hexagonal.

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 has no horizontal segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 6:30, Master = 18:00, Expert = 36:00

Solution: PDF; a solution video is available here.

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.

PDF

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

Theme: 2×2 Welcome! (for Jamie Hargrove)

Author/Opus: This is the 25th puzzle from our contributing puzzlemaster John Bulten.

Rules: Variation of Nurikabe rules. The 2×2 shaded cell rule no longer applies. In its place, it is not allowed to have five consecutive black cells in any row or column.

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 = 7:30, Master = 13:00, Expert = 26:00

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.

(view directly for a larger image)

PDF

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

Theme: Five Stars

Author/Opus: This is the 66th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Same as LITS, except that each region must contain two shaded tetrominoes. These two tetrominoes within a region cannot touch each other, and can be the same or different shapes.

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 = 12:00, Master = 18:30, Expert = 37:00

Solution: PDF

Note: Follow this link for more variations of LITS and this link for classic LITS. If you are new to this puzzle type, here are our easiest LITS to get started on. More LITS puzzles can be found in LOTS O’ LITS by Grant Fikes and Prasanna Seshadri and in The Art of Puzzles 2.

PDF

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

Theme: Which Way is Right?

Author/Opus: This is the 23rd puzzle from our contributing puzzlemaster John Bulten.

Rules: Same as LITS, except that each region must contain two shaded tetrominoes. These two tetrominoes within a region cannot touch each other, and can be the same or different shapes.

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 = 20:00, Expert = 40:00

Solution: PDF

Note: Follow this link for more variations of LITS and this link for classic LITS. If you are new to this puzzle type, here are our easiest LITS to get started on. More LITS puzzles can be found in LOTS O’ LITS by Grant Fikes and Prasanna Seshadri and in The Art of Puzzles 2.