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: Logical theme encountered during the solve

Rules: Standard Masyu 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 = 0:40, Master = 1:00, Expert = 2:00

Solution: PDF

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: 4×4×4 – a puzzle with symmetric odd clue squares along the main diagonal.

Rules: Standard Cave rules.

Answer String: Enter the length in cells of each of the cave 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 = 5:15, Master = 8:15, Expert = 16:30

Solution: PDF

Note: Follow 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)

This is a “Franken-Friday” puzzle variation.

Theme: Logical

Rules: Standard Cross the Streams rules, except that the puzzle uses an early number system that only has the concepts of “one” and “many”. All number clues greater than 1 are represented by a + symbol.

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 = 3:15, Master = 6:30, Expert = 13:00

Solution: PDF

Editorial Note: This variation was inspired by a puzzle on a recent Tapa Variations Contest by Serkan Yürekli. A new Tapa Variations Contest runs this weekend for those that are interested.

PDF

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

Theme: Clockwise Threes

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 = 2:00, Master = 5:00, Expert = 10:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode 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: Four Blocks

Rules: Standard Tapa rules.

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 = 1:40, Master = 2:15, Expert = 4:30

Solution: PDF

PDF

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

Theme: Two Sides (the shading is just for artistic effect)

Rules: Standard LITS rules.

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 = 1:20, Master = 1:45, Expert = 3:30

Solution: PDF

PDF

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

Theme: Even/Odd Clover

Rules: Standard Sudoku rules.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:45, Expert = 9:30

Solution: PDF

Note: This puzzle is probably harder than a typical Monday, but was the style we always had in mind for 9/9, which the World Puzzle Federation recently set as “International Sudoku Day”. Happy solving! Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

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

Theme: 4x4x4 – A puzzle with lots of tetromino cages packed into 4×4 squares.

Rules: Standard TomTom rules, using digits from 1-8.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 7th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 6:00, Master = 7:45, Expert = 15:30

Solution: PDF

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

PDF

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

This is a “Franken-Friday” puzzle variation.

Theme: Logical

Rules: Variation of standard Slitherlink rules. Exactly one clue in each row and column is lying and must represent a different number.

Answer String: Enter the length in cells of each of the internal loop 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 = 6:45, Master = 12:00, Expert = 24:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode 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: 4×4 Clueless Square

Rules: Standard Tapa rules.

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 entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 3:45, Expert = 7:30

Solution: PDF