Nanro Loop by Bryce Herdt

Nanro by Bryce Herdt

PDF

or solve online (using our beta test of Penpa-Edit tools; use the tab key to alternate between shading, number entry, and composite loop drawing modes)

Theme: Parquet

Author/Opus: This is the 23rd puzzle from guest contributor Bryce Herdt.

Rules: Variation of Nanro rules. Label some cells with numbers to form a single non-intersecting loop; no 2×2 group of cells may be fully labeled, but the loop may touch itself orthogonally or diagonally. The region boundaries divide the loop into segments, and each region must have at least one segment. Numbers denote the length in cells of each segment within a region; all numbers in a region must be the same. When two numbers from different segments are orthogonally adjacent, the numbers must be different. (Consequently, segments in the same region must not share an edge.)

Also see this example:

Nanro Loop Example by Serkan Yürekli

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 6:15, Master = 9:15, Expert = 18:30

Solution: PDF and solving video.

Note: Follow this link for Nanro puzzles on this website and this link for variations on Nanro puzzles. If you are new to this puzzle type, here are our easiest Nanro Puzzles to get started on. More Nanro puzzles can be found in A Number o’ Nanro by Prasanna Seshadri.

Nanro by David Altizio

Nanro by David Altizio

PDF

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

Theme: Twelve Hexominoes

Author/Opus: This is the 12th puzzle from guest contributor David Altizio.

Rules: Standard Nanro rules.

Difficulty: 2.5 stars

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

Solution: PDF and solving video.

Note: Follow this link for Nanro puzzles on this website and this link for variations on Nanro puzzles. If you are new to this puzzle type, here are our easiest Nanro Puzzles to get started on. More Nanro puzzles can be found in A Number o’ Nanro by Prasanna Seshadri.

Killer / Thermo-Sudoku by Michael Rios

Killer / Thermo-Sudoku by Michael Rios

PDF

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

Theme: Sudoku Crew

Author/Opus: This is the 4th puzzle from guest contributor Michael Rios.

Rules: Standard Killer Sudoku rules and Thermo-Sudoku rules. Specifically, insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. Also, the sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage. Some thermometer shapes are in the grid; numbers must be strictly increasing from the round bulb to the flat end.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 7:30, Master = 11:15, Expert = 22:30

Solution: PDF and solving video.

Note: Follow this link for more Killer Sudoku and this link for classic Sudoku. More Killer Sudoku puzzles can be found in Killer Sudoku by Serkan Yürekli. Follow this link for more Thermo-Sudoku puzzles. If you are new to this puzzle type, here are our easiest Thermo-Sudoku to get started on. More Thermo-Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 2.

Kuromasu by Salih Alan

Kuromasu by Salih Alan

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: Antisymmetry

Author/Opus: This is the 20th puzzle from guest contributor Salih Alan.

Rules: Shade some empty cells black so that each number indicates the total count of white cells connected vertically and horizontally to that number including the numbered cell itself. Black cells cannot share an edge, and all white cells must belong to a single connected group.

Also see this example:

Kuromasu by Thomas Snyder

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 3:30, Expert = 7:00

Solution: PDF and solving video.

Note: Follow this link for more Kuromasu puzzles. More Kuromasu can be found in Grandmaster Puzzles Quarterly Vol. 3.

Kuromasu by Sam Cappleman-Lynes

Kuromasu by Sam Cappleman-Lynes

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: Twins

Author/Opus: This is the 14th puzzle from guest contributor Sam Cappleman-Lynes.

Rules: Shade some empty cells black so that each number indicates the total count of white cells connected vertically and horizontally to that number including the numbered cell itself. Black cells cannot share an edge, and all white cells must belong to a single connected group.

Also see this example:

Kuromasu by Thomas Snyder

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 1:45, Master = 2:30, Expert = 5:00

Solution: PDF and solving video.

Note: Follow this link for more Kuromasu puzzles. More Kuromasu can be found in Grandmaster Puzzles Quarterly Vol. 3.

Sunday Stumper: Yajilin by Sam Cappleman-Lynes

Since 2021, we have posted some extra difficult Sunday Stumpers, about once a month. These will be quite tough puzzles, but with a logical path to be found (and solution videos to help). This twelfth Sunday Stumper of 2022 is a Yajilin puzzle by Sam Cappleman-Lynes with a tricky path into and out from the “Open Middle”.

Yajilin by Sam Cappleman-Lynes

(view directly for a larger image)

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: Open Middle

Author/Opus: This is the 13th puzzle from guest contributor Sam Cappleman-Lynes.

Rules: Standard Yajilin rules.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 8:30, Master = 12:30, Expert = 25:00

Solution: PDF and solving video.

Note: Follow this link for classic Yajilin and this link for Yajilin variations. If you are new to this puzzle type, here are our easiest Yajilin to get started on. More Yajilin puzzles can be found in The Art of Puzzles 2, in Yajilin by Murat Can Tonta and Prasanna Seshadri, and in our beginner-friendly book Logic Puzzles 101.

Yajilin by David Altizio

Yajilin by David Altizio

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: 4×4 Grid

Author/Opus: This is the 11th puzzle from guest contributor David Altizio.

Rules: Standard Yajilin rules.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 7:00, Master = 9:45, Expert = 19:30

Solution: PDF and solving video.

Note: Follow this link for classic Yajilin and this link for Yajilin variations. If you are new to this puzzle type, here are our easiest Yajilin to get started on. More Yajilin puzzles can be found in The Art of Puzzles 2, in Yajilin by Murat Can Tonta and Prasanna Seshadri, and in our beginner-friendly book Logic Puzzles 101.