Sunday Stumper: Shape Sudoku by Salih Alan

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 eighth Sunday Stumper of 2022 is a Shape Sudoku by Salih Alan with a “Multiplication” theme in each of the shapes; while it might be a touch easier at 4.5 stars than some of our other stumpers, we expect you’ll still enjoy figuring out the intended solving path.

Shape Sudoku by Salih Alan

PDF

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 manage the shape inventory.)

Theme: Multiplication

Author/Opus: This is the 16th puzzle from guest contributor Salih Alan.

Rules: Standard Sudoku rules. Also, there are some numbered shapes that must be put into the grid. Shapes can be rotated, but cannot be reflected.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 9:00, Master = 15:00, Expert = 30:00

Solution: PDF and solving video.

Note: Follow this link for other Shape Sudoku. More Shape Sudoku are in Masterpiece Sudoku Mix 8.

Shape Sudoku by Thomas Snyder

Shape Sudoku by Thomas Snyder

PDF

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 manage the shape inventory.)

Theme: Offset Frame

Author/Opus: This is the 418th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules. Also, there are some numbered shapes that must be put into the grid. Shapes can be rotated, but cannot be reflected.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 8:30, Master = 13:00, Expert = 26:00

Solution: PDF and solving video.

Note: Follow this link for other Shape Sudoku. More Shape Sudoku are in Masterpiece Sudoku Mix 8.

Shape Sudoku by Serkan Yürekli

Shape Sudoku by Serkan Yürekli

PDF

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 manage the shape inventory.)

Theme: Goalkeeper

Author/Opus: This is the 374th puzzle from our managing editor Serkan Yürekli.

Rules: Standard Sudoku rules. Also, there are some numbered shapes that must be put into the grid. Shapes can be rotated, but cannot be reflected.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 1:45, Expert = 3:30

Solution: PDF and solving video.

Note: Follow this link for other Shape Sudoku. More Shape Sudoku are in Masterpiece Sudoku Mix 8.

Shape Sudoku by Serkan Yürekli

Sudoku by Serkan Yürekli

PDF

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 manage the shape inventory.)

Theme: Four Squares (Originally on 2017 Brand’s Sudoku Open)

Author/Opus: This is the 167th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Standard Sudoku rules. Also, there are some numbered shapes that must be put into the grid. Shapes can be rotated, but cannot be reflected.

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

Time Standards (highlight to view): Grandmaster = 4:15, Master = 11:45, Expert = 23:30

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.

Arrow/Shape/Thermo-Sudoku by Prasanna Seshadri

Sudoku by Prasanna Seshadri

PDF

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

Theme: Diamonds (for Chris Green)

Author/Opus: This is the 150th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Classic Sudoku Rules. Also, some arrow shapes are in the grid; the sum of the digits along the path of each arrow must equal the digit in the circled cell. Some thermometer shapes are in the grid; digits must be strictly increasing from the round bulb to each flat end. Finally, some diamond shapes are in the grid; the labeled diamonds below the grid must be placed in some order onto the shapes in the grid. The labeled diamonds can be rotated but cannot be reflected.

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

Time Standards (highlight to view): Grandmaster = 5:15, Master = 10:45, Expert = 21:30

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. More Arrow and Thermo-Sudoku puzzles can be found in The Art of Sudoku 2.

Hidden Shape Sudoku by John Bulten

Sudoku by John Bulten

(View image directly for larger form.)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku number entry mode and two drawing modes, Special and Surface, to mark the shape inventory.)

Theme: Snakes on a Sudoku

Author/Opus: This is the 16th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Sudoku rules. Also, there are some shapes that must be put into the grid. The shapes can be rotated, but cannot be reflected; they can touch but cannot overlap. (Not all cells of the shapes contain numbers, but all numbers on the shapes must be entered into the corresponding cells after placement.)

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th row from left to right.

Time Standards (highlight to view): Grandmaster = 10:00, Master = 30:00, Expert = 60:00

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.

Hidden Shape Sudoku by John Bulten

Sudoku by John Bulten

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku number entry mode and two modes, Shape and Surface, to manage the domino inventory.)

Theme: Double Domino
(Hidden shapes include a complete double-eight domino set. Double dominoes have been “doubled over” to fit within one square. Hidden names include J.S. Bach, Gabriel Faure, John Cage, and various chordal progressions and crossword game vocabulary.)

Author/Opus: This is the 9th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Sudoku rules, using the letters A-H and a blank. Also, as in Shape Sudoku, there are some lettered shapes given beneath the grid that must be put in their proper places inside the grid; and, as in Battleship Sudoku, their proper places are indicated only partially. (Partial shape clues in the grid are not lettered but do not necessarily indicate the location of blanks.) The shapes can be rotated, but cannot be reflected; they can touch but cannot overlap.

Answer String: Enter the 3rd row from left to right, followed by a comma, followed by the 3rd column from top to bottom. (Use the capital letters A-H; use X for a blank.)

Time Standards (highlight to view): Grandmaster = 12:00, Master = 21:00, Expert = 42:00

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.