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 tenth Sunday Stumper of 2022 is a Tapa-Like Loop (Transparent) puzzle by Prasanna Seshadri. Will all the cells be used in this puzzle like the title and the clues suggest?

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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 on edges)

Theme: All Cells?

Author/Opus: This is the 243rd puzzle from contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of Tapa-Like Loop rules. (Form a single non-intersecting loop. Clues inside the grid represent the number of neighboring cells visited by the loop; if there is more than one number in a cell, each number should be represented with a separate loop segment. There is no 2×2 rule of Tapa in this puzzle.)

The loop can travel through clue cells. Each clue now describes the entire 3×3 area the clue cell is in the middle of.

See also this example:

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 32:00, Master = 45:00, Expert = 1:30:00

Solution: PDF and solving video.

Note: Follow this link for other Tapa-Like Loop puzzles. More Tapa-Like Loop puzzles can be found in the Tapa-Like Loop Collection by Prasanna Seshadri.

PDF

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

Author/Opus: This is the 242nd puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Pentopia rules: Place some of the given pentominoes in the grid so that no pentominoes are in adjacent cells that share an edge or corner. Pentominoes cannot repeat in the grid; rotations and reflections of a pentomino are considered the same shape. The arrow clues indicate all the directions (up, down, left, and right) where the nearest pentominoes are located when looking from that square. (Arrow clues cannot contain pentomino shapes.) Also, see this example:

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 5:30, Master = 8:30, Expert = 17:00

Solution: PDF and solving video.

Note: Follow this link for more Pentopia puzzles and this link for other puzzles involving Pentominoes.

PDF

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

Theme: The Lonely Ones

Author/Opus: This is the 422nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard TomTom rules, using the integers 1-6.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 4:15, Master = 7:00, Expert = 14:00

Solution: PDF and solving video.

Note: Follow this link for classic TomTom and this link for TomTom variations. If you are new to this puzzle type, here are our easiest TomTom to get started on. More TomTom puzzles can be found in the TomTom collection, in The Art of Puzzles, 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: Question Marks

Author/Opus: This is the 18th puzzle from guest contributor Rajesh Kumar.

Rules: Standard Arrow Sudoku rules.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 5:15, Master = 9:00, Expert = 18:00

Solution: PDF and solving video.

Note: Follow this link for more Arrow Sudoku. If you are new to this puzzle type, here are our easiest Arrow Sudoku to get started on. More Arrow Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 3.

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 on edges)

Theme: Groups of Three

Author/Opus: This is the 25th puzzle from our contributing puzzlemaster Takeya Saikachi.

Rules: Variation of Tapa: Form a single non-intersecting loop. Clues inside the grid represent the number of neighboring cells visited by the loop; if there is more than one number in a cell, each number should be represented with a separate loop segment. There is no 2×2 rule of Tapa in this puzzle.

See also this example:

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 3:45, Expert = 7:30

Solution: PDF and solving video.

Note: Follow this link for other Tapa-Like Loop puzzles. More Tapa-Like Loop puzzles can be found in the Tapa-Like Loop Collection by Prasanna Seshadri.

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: Plus

Author/Opus: This is the 55th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Aqre rules: Shade some cells so that all shaded cells form one connected group. Regions with numbers must contain the indicated count of shaded cells, and it is allowed to shade over the numbered cells. There may not exist a run of four or more consecutive shaded or unshaded cells horizontally or vertically anywhere in the grid.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 1:45, Master = 3:00, Expert = 6:00

Solution: PDF and solving video.

Note: Follow this link for more Aqre puzzles. If you are new to this puzzle type, here are our easiest Aqre to get started on. More Aqre puzzles are in Shading Variety Collection by Prasanna Seshadri.

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 shading mode.)

Theme: Brackets

Author/Opus: This is the 386th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Araf rules.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:00, Master = 1:15, Expert = 2:30

Solution: PDF and solving video.

Note: Follow this link for more Araf puzzles on this website. If you are new to this puzzle type, here are our easiest Araf Puzzles to get started on. More Araf puzzles can be found in the ebook Araf by Serkan Yürekli.

PDF

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

Author/Opus: This is the 99th puzzle from our contributing puzzlemaster Ashish Kumar.

Rules: Standard Outside Sudoku rules: Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. Some numbers are given outside the grid. These numbers must appear in the first three cells in the corresponding direction.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 6:00, Master = 10:45, Expert = 21:30

Solution: PDF and solving video.

Note: Follow this link for more Outside Sudoku puzzles. More Outside Sudoku puzzles can be found in Masterpiece Sudoku Mix 4.

PDF

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

Theme: Triangles

Author/Opus: This is the 6th puzzle from guest contributor R. Kumaresan.

Rules: Standard Sudoku rules.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 6:30, Master = 9:00, Expert = 18:00

Solution: PDF and solving video.

Note: 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: Up and Down

Author/Opus: This is the 17th puzzle from guest contributor Zoltán Horváth.

Rules: Standard Arrow Sudoku rules.

Difficulty: 3 stars

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:15, Expert = 10:30

Solution: PDF and solving video.

Note: Follow this link for more Arrow Sudoku. If you are new to this puzzle type, here are our easiest Arrow Sudoku to get started on. More Arrow Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 3.