Note: This puzzle is a contest puzzle. All correctly submitted answers (in the applet below the puzzle) before November 9th will be entered into the contest drawing. Two solvers will each get a Grandmaster Puzzles/Thomas Snyder puzzle book of their choice.

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PDF

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

Theme: 200th Puzzle Contest Spectacular

Author/Opus: This is the 200th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: To be determined by solver. (Edit: the full rules are now available on this post.)

Answer String: Enter the final answer as a single string of twelve capital letters.

Time Standards (highlight to view): Grandmaster = 20:00, Master = 35:00, Expert = 1:10:00

Solution: PDF

Note: Follow this link for classic TomTom puzzles. 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)

Theme: Invaluable

Author/Opus: This is the 2nd puzzle from guest contributor John Bulten.

Rules: Standard TomTom rules, using the integers 1-5. Also, each cage must have a non-negative integer operation value (i.e., is equal to 0, 1, 2, 3, 4, …).

Answer String: Enter the 1st row from left to right followed by the 2nd row from left to right. Separate all rows with a comma.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 7:00, Expert = 14:00

Solution: PDF

Note: Follow this link for variations of TomTom and this link for more 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; in default linex mode: left-click+drag draws line, right click marks X on edge)

Theme: To The Nines

Author/Opus: This is the 8th puzzle from guest contributor Craig Kasper.

Rules: Draw a single loop in the grid which may cross itself orthogonally, but otherwise does not touch or retrace itself. The clue numbers to the left/right of the rows indicate the number of squares visited by the nearest section of the loop that travels horizontally in the rows. The clue numbers to the top/bottom of the columns indicate the number of squares visited by the nearest section of the loop that travels vertically in the columns.

Also, see this example:

Answer String: Enter the number of empty squares for each row from top to bottom, followed by a comma, and then the number of turns for each row from top to bottom. This example has the key “100000,422224”.

Time Standards (highlight to view): Grandmaster = 4:45, Master = 7:00, Expert = 14:00

Solution: PDF

Note: Follow this link for other Round Trip puzzles. Some more Round Trip puzzles can be found in the book Loop Variety Collection by Ashish Kumar and Murat Can Tonta.

PDF

or solve online (using our beta test of Penpa-Edit tools; use Tab key to alternate between line drawing and shading)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 60th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Nurikabe. Shade some empty cells black so that the grid is divided into white areas, each containing at most one number. A white area with a number must have the same area in cells as that number. White areas may only touch diagonally. All shaded cells must be connected with each other, but no 2×2 group of cells can be entirely shaded. Also, all shaded cells must be divisible into snakes with the heads and tails given in the grid. Snakes cannot cross each other.

Also, see this example:

Answer String: Enter the length in cells of each of the black segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma. This example has the key “7,32,31”.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 10:00, Expert = 20:00

Solution: PDF

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

PDF

or solve online (using our beta test of Penpa-Edit tools; in default linex mode: left-click+drag draws line, right click marks X on edge)

Theme: Odd Lots

Author/Opus: This is the 7th puzzle from guest contributor Craig Kasper.

Rules: Draw a single loop in the grid which may cross itself orthogonally, but otherwise does not touch or retrace itself. The clue numbers to the left/right of the rows indicate the number of squares visited by the nearest section of the loop that travels horizontally in the rows. The clue numbers to the top/bottom of the columns indicate the number of squares visited by the nearest section of the loop that travels vertically in the columns.

Also, see this example:

Answer String: Enter the number of empty squares for each row from top to bottom, followed by a comma, and then the number of turns for each row from top to bottom. This example has the key “100000,422224”.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:00, Expert = 10:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Round Trip puzzles. Some more Round Trip puzzles can be found in the book Loop Variety Collection by Ashish Kumar and Murat Can Tonta.

PDF

or solve online (using our beta test of Penpa-Edit tools; use Tab key to alternate between line drawing and shading)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 59th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Nurikabe. Shade some empty cells black so that the grid is divided into white areas, each containing at most one number. A white area with a number must have the same area in cells as that number. White areas may only touch diagonally. All shaded cells must be connected with each other, but no 2×2 group of cells can be entirely shaded. Also, all shaded cells must be divisible into snakes with the heads and tails given in the grid. Snakes cannot cross each other.

Also, see this example:

Answer String: Enter the length in cells of each of the black segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma. This example has the key “7,32,31”.

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

Solution: PDF

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

PDF

or solve online (using our beta test of Penpa-Edit tools; in default linex mode: left-click+drag draws line, right click marks X on edge)

Theme: Getting Even

Author/Opus: This is the 6th puzzle from guest contributor Craig Kasper.

Rules: Draw a single loop in the grid which may cross itself orthogonally, but otherwise does not touch or retrace itself. The clue numbers to the left/right of the rows indicate the number of squares visited by the nearest section of the loop that travels horizontally in the rows. The clue numbers to the top/bottom of the columns indicate the number of squares visited by the nearest section of the loop that travels vertically in the columns.

Also, see this example:

Answer String: Enter the number of empty squares for each row from top to bottom, followed by a comma, and then the number of turns for each row from top to bottom. This example has the key “100000,422224”.

Solution: PDF

Time Standards (highlight to view): Grandmaster = 3:30, Master = 6:00, Expert = 12:00

Note: Follow this link for other Round Trip puzzles. Some more Round Trip puzzles can be found in the book Loop Variety Collection by Ashish Kumar and Murat Can Tonta.

PDF

or solve online (using our beta test of Penpa-Edit tools; use Tab key to alternate between line drawing and shading)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 58th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Nurikabe. Shade some empty cells black so that the grid is divided into white areas, each containing at most one number. A white area with a number must have the same area in cells as that number. White areas may only touch diagonally. All shaded cells must be connected with each other, but no 2×2 group of cells can be entirely shaded. Also, all shaded cells must be divisible into snakes with the heads and tails given in the grid. Snakes cannot cross each other.

Also, see this example:

Answer String: Enter the length in cells of each of the black segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma. This example has the key “7,32,31”.

Time Standards (highlight to view): Grandmaster = 0:45, Master = 1:15, Expert = 2:30

Solution: PDF

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

PDF

or solve online (using our beta test of Penpa-Edit tools; in default linex mode: left-click+drag draws line, right click marks X on edge)

Theme: Taking Sides

Author/Opus: This is the 5th puzzle from guest contributor Craig Kasper.

Rules: Draw a single loop in the grid which may cross itself orthogonally, but otherwise does not touch or retrace itself. The clue numbers to the left/right of the rows indicate the number of squares visited by the nearest section of the loop that travels horizontally in the rows. The clue numbers to the top/bottom of the columns indicate the number of squares visited by the nearest section of the loop that travels vertically in the columns.

Also, see this example:

Answer String: Enter the number of empty squares for each row from top to bottom, followed by a comma, and then the number of turns for each row from top to bottom. This example has the key “100000,422224”.

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:30, Expert = 3:00

Solution: PDF

Note: Follow this link for other Round Trip puzzles. Some more Round Trip puzzles can be found in the book Loop Variety Collection by Ashish Kumar and Murat Can Tonta.

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: Logical

Author/Opus: This is the 1st puzzle from guest contributor Ashish Kumar.

Rules: Locate a snake of unknown length in the grid, whose head, tail, and exact center are given. The snake does not touch itself, even diagonally. Numbers outside the grid indicate the number of snake cells in that row/column.
See also this example:

Answer String: Enter the length in cells of each of the snake segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma. This example has the key “211,31”.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 9:30, Expert = 19:00

Solution: PDF