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Theme: Clue Symmetry and Logic

Author/Opus: This is the 137th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Tight Fit Sudoku rules with digits from 1-9. There are five grids with these extra rules:

– Even/Odd (upper-left): Digits in circles must be odd and digits in squares must be even.
– No Touch (upper-right): Digits cannot repeat in diagonally adjacent cells (both digits in any “tight fit” cell are considered when checking presence in a diagonally adjacent cell). Only look within the upper-right grid when applying this rule.
– Irregular (center): Instead of 3×2 borders, the bold regions are irregularly shaped (and colored in cyan).
– Anti-Knight (lower-left): Digits cannot repeat in any cells separated by a chess knight’s move (both digits in any “tight fit” cell are considered when checking for presence in a cell a knight’s move away). Only look within the lower-left grid when applying this rule.
– Killer (lower-right): There are some dotted cages; the number clues given with these cages indicate the sum of all digits in the cage. Digits cannot repeat within a given cage.

Answer String: Enter the 2nd row in the even/odd from left to right, followed by a comma, followed by the 4th row in the no touch from left to right, followed by a comma, followed by the 3rd row in the irregular from left to right, followed by a comma, followed by the 5th row in the anti-knight from left to right, followed by a comma, followed by the 6th row in the killer from left to right. (Note: for the tight fit cells, enter the top before the bottom as would be normal for the read order.)

Time Standards (highlight to view): Grandmaster = 22:30, Master = 40:00, Expert = 1:20:00

Solution: PDF

Note: Follow this link for other Tight Fit Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Tight Fit Sudoku to get started on. More Tight Fit Sudoku can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in The Art of Sudoku 2.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku = big entries and Number candidate = small entries in the corners of cells.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 136th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Tight Fit Sudoku rules with digits from 1-9. Also, there are some dotted cages; the number clues given with these cages indicate the sum of all digits in the cage. Digits cannot repeat within a given cage.

Answer String: Enter the 6th row from left to right, followed by a comma, followed by the 6th column from top to bottom. (Note: for the tight fit cells, enter the top before the bottom as would be normal for the read order.)

Time Standards (highlight to view): Grandmaster = 5:30, Master = 9:30, Expert = 19:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Tight Fit Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Tight Fit Sudoku to get started on. More Tight Fit Sudoku can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in The Art of Sudoku 2.

PDF

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

Theme: 1 to 9 (for patron Veep, who co-wrote this style for the 2016 MIT Mystery Hunt)

Author/Opus: This is the 130th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Fill each cell with a digit from 1 to 9 (1 to 6 in example) so that no digit repeats in any row or column, and also draw a single, non-intersecting loop through some of the cells in the grid. The loop cannot pass through gray cells. Numbers on the outside of the grid show the sum of digits of ALL horizontal/vertical loop segments in that row/column in order. (Note: as in column 5 of the example, only segments that pass horizontally/vertically in a row/column appear as clues; the 5 in that column is not part of a vertical segment and is not represented by a clue). Not all outside clues are given, and unclued rows/columns can have any possible distribution of loop segments/sums.

Answer String: Enter the digits in the 1st row from left to right, followed by a comma, followed by the 6th row from left to right.

Time Standards (highlight to view): Grandmaster = 9:15, Master = 14:00, Expert = 28:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other less common Number Placement puzzles.

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

Theme: Anti-XV (for patron Phleb)

Author/Opus: This is the 129th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Sudoku rules. Also, when the numbers in two cells sharing an edge add up to 5, a V is marked on that edge; when the numbers in two cells sharing an edge add up to 10, an X is marked on that edge. (For clarity, as no symbols appear in the grid below, there are never any edge-adjacent cells that sum to 5 or 10.)

Answer String: Enter the 6th row from left to right, followed by a comma, followed by the 5th column from top to bottom.

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

Solution: PDF

Note: Follow this link for other 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.

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or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a shading mode and 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: Horizontal Hold

Author/Opus: This is the 220th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Cross the Streams rules. Also, the shaded region must be able to be split into tetrominoes to form a valid LITS solution (meaning all tetrominoes are connected but no two tetrominoes sharing an edge are the same shape, including rotations and reflections).

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 = 6:00, Master = 8:15, Expert = 16:30.

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.

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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: Logical

Author/Opus: This is the 219th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Combination of Pentominous and Star Battle. Place stars into some cells so that there are two stars in each row and column; no two stars can touch, even diagonally. Then divide the rest of the grid into 16 regions each containing 5 cells. Regions with the same shape (including rotations/reflections) cannot share an edge. A cell with a letter in it must be part of the pentomino shape normally associated with that letter; an inventory of pentominoes is given below the puzzle.

Answer String: Enter the letter associated with the pentomino occupying each cell or an asterisk (*) if it is a star in the marked rows from left to right, separating the groups with a comma. Use CAPITAL LETTERS! Example: IIIII*LFF*,TTT*PP*VVV

Time Standards (highlight to view): Grandmaster = 4:45, Master = 8:15, Expert = 16:30

Solution: PDF; a solution video is available here.

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

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

Theme: Clue Symmetry and Logic

Author/Opus: This is the 127th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Hybrid of Japanese Sums and Latin Squares. Place a digit from 1-6 (1-4 in the example) into some cells so that each digit appears exactly once in each row and column. Numbers outside the grid indicate the sums of all adjacent digits in order in that row or column.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th column from top to bottom. Use a capital X for empty cells.

Time Standards (highlight to view): Grandmaster = 4:45, Master = 7:30, Expert = 15:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Japanese Sums puzzles.

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

Theme: Area 29

Author/Opus: This is the 126th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Kakuro Rules.

Answer String: Enter the values in each white cell in the marked row from left to right and then the marked column from top to bottom, separating the groups with a comma.

Time Standards (highlight to view): Grandmaster = 4:30, Master = 6:45, Expert = 13:30

Solution: PDF

Note: Follow this link for other Kakuro puzzles.

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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: Salt and Pepper (alphanumerically, 19 = S, 16 = P)

Author/Opus: This is the 18th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Fillomino rules. Also, all polyominoes should have rotational symmetry as in this example:

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Enter just the last digit for any two-digit number. Start with the 1st row, followed by a comma, followed by the 10th column.

Time Standards (highlight to view): Grandmaster = 10:00, Master = 22:30, Expert = 45:00

Solution: PDF; a solution video is available here.

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

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

Theme: No Zeroes

Author/Opus: This is the 132nd puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of Sudoku. Instead of the digits 1 through 9, this puzzle uses the digits 1 through 7 as well as two black squares in each row, column, and bold region. Clues outside the grid indicate the sum of all digits between the black squares in that row/column.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th row from left to right. Use a capital X for all black squares.

Time Standards (highlight to view): Grandmaster = 8:30, Master = 10:30, Expert = 21:00

Solution: PDF

Note: 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.