PDF

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

Theme: Sudoku GP Round 7, plus two hidden themes related to 7
(Note: this puzzle was originally created for the Sudoku Grand Prix but after testing was judged too hard and too puzzle-based for the competition. It is an excellent puzzle, and we are proud to showcase it here.)

Author/Opus: This is the 40th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Sudoku rules. Also, standard Skyscrapers rules. Additionally, the cells in gray are “underground” and cannot be seen by any of the outside skyscraper clues (think of them as starting with a negative sign if necessary). As an example, the 3 on the left of row 2 refers only to seeing three buildings in columns 2 through 9, even if there is a 9 in column 1 as that 9 cannot be seen.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 10:00, Expert = 20:00

Solution: PDF

Note: Follow this link for our first Basement Skyscraper Sudoku. Follow this link for other less common variations of Sudoku and this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

Note: When we said everything was a lie in last week’s schedule, that included there being just 6 puzzles. Enjoy this bonus ‘Sunday’ challenge from Prasanna.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode, a number entry mode for placing Tapa clues, and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 38th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of Tapa Rules. Every given clue is lying in two ways: first, the number of given clues in that cell is false; second, the value of any given clues is not true for any part of the Tapa around that cell. For example, a 3 clue could actually indicate 24, but it could not indicate 2 (same number of clues) or 23 (the digit 3 appears). 0 is not a valid clue for this Tapa.

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 = 8:00, Master = 16:00, Expert = 32:00

Solution: PDF

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

PDF

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

Theme: Logical

Author/Opus: This is the 123rd puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Variation of Cross the Streams rules. Some groups of outside clues are lying and refer to the white cells in that row/column, not the black cells. It is up to you to determine which clue groups are lies. (It is possible for a clue group to be true for both the white and black cells in that row/column.)

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

Time Standards (highlight to view): Grandmaster = 5:30, Master = 9:00, Expert = 18:00

Solution: PDF

Note: Follow this link for regular 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 tab to alternate between a composite mode for line/edge drawing and a letter entry mode.)

Theme: Words

Author/Opus: This is the 55th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Divide the grid into 20 regions each containing 5 cells. Regions with the same shape (including rotations/reflections) cannot share an edge. A region may contain at most one letter clue. Each letter is false; the correct letter which indicates the shape of that pentomino is either one higher or one lower in alphabetical order (for instance, a P clue could be an N or a T pentomino).

Answer String: Enter the letter associated with the pentomino occupying each cell in the two marked rows from left to right, separating the rows with a comma. Use CAPITAL LETTERS!

Time Standards (highlight to view): Grandmaster = 5:45, Master = 7:30, Expert = 15:00

Solution: PDF

Note: Follow this link for other puzzles involving Pentominoes.

PDF

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

Theme: Logical

Author/Opus: This is the 37th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of LITS rules. Every region here is a lie: while exactly four cells must be shaded in each bold region, they do not form an L, I, T, or S tetromino. (Note: the other rules still apply. There must be a single connected group of shaded cells, divisible into L, I, T, and S tetrominoes so that no two identical tetrominoes touch and no 2×2 block of cells is completely shaded.)

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 = 5:00, Expert = 10:00

Solution: PDF

Note: Follow 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)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 54th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Sudoku rules. Every given clue is lying. The correct value is either one more or one less than the given clue. (1 clues cannot become 0, and 9 clues cannot become 10.)

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 5:30, Master = 8:00, Expert = 16:00

Solution: PDF

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

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: Think Carefully about 24!

Author/Opus: This is the 53rd puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Fillomino rules. Every given clue is lying. The correct value is either one more or one less than the given clue. (1 clues cannot become 0.)

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Start with the 3rd row, followed by a comma, followed by the 6th row.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:00, Expert = 8:00

Solution: PDF

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

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 6th puzzle from guest contributor Hans van Stippent.

Rules: Variation of Masyu rules. Exactly one circle clue in every row and column is lying. If a lying clue is a white circle, it should be black instead. If a lying clue is a black circle, if should be white instead.

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 = 2:45, Master = 3:30, Expert = 7:00

Solution: PDF

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

PDF

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

Theme: One, Two

Author/Opus: This is the 3rd puzzle from guest contributor Tapio Saarinen, including one earlier Outside Nurikabe. You can find more of his puzzles on Perplexible.

Rules: In this variation of Nurikabe, the island clues are now given outside the grid. These numbers must be placed in the first white island cell encountered in the corresponding direction. Each number represents a distinct island, with a total of 23 islands in this puzzle.

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 = 4:15, Master = 10:00, Expert = 20:00

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.

PDF

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 52nd puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Nurikabe. Place all 12 pentominoes into the grid as Nurikabe islands (rotations and reflections allowed), with no other islands. Pentominoes may be indicated by one or more letter clues, or by no letters at all.

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 = 4:00, Master = 5:15, Expert = 10:30

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.