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.

PDF

Theme: Logical

Author/Opus: This is the 1st puzzle from guest contributor Dan Adams.

Rules: Place digits into some cells and shade all remaining cells so that: each dodecagon contains the digits 1-9 exactly once; digits in cells sharing a vertex with a black triangle add up to the indicated clue number without repeats; and shaded cells cannot share an edge with another shaded cell.

Answer String: Enter the digits in the marked central rows (triangle, hexagon, triangle, …). Use a capital X for shaded cells. Separate each row with a comma. The example has the key “8178XX,243”.

Time Standards (highlight to view): Grandmaster = 16:00, Master = 32:00, Expert = 1:04:00

Solution: PDF

Note: Follow this link for other less common Number Placement puzzles.

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: Clue Symmetry and Logic

Author/Opus: This is the 7th puzzle from guest contributor Walker Anderson.

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 = 3:45, Master = 8:45, Expert = 17:30

Solution: PDF; a solution video is available here.

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. More Cave puzzles can be found in The Art of Puzzles and in Roger Barkan’s Colossal Cave Collection.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between multiple modes including a shading mode, the linex mode where left click+drag draws lines and right click marks X’s, a shape entry mode, and a number entry mode)

Theme: Logical

Author/Opus: This is the 6th puzzle from guest contributor Roger Barkan.

Rules: Combination of Star Battle and Cave. Place digits into two cells in every row, column, and region of the top grid (one cell in the example). Digits cannot touch, not even diagonally. The numbers in the upper-left of each region indicate the identity of the digit to be entered in that region. The digits must form a valid cave puzzle (which can be solved on the bottom grid).

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 = 9:00, Master = 15:30, Expert = 31:00

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. More Cave puzzles can be found in The Art of Puzzles and in Roger Barkan’s Colossal Cave Collection.

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: Clue Symmetry and Logic (Puzzle #63 in the Colossal Cave Collection).

Author/Opus: This is the 5th puzzle from guest contributor Roger Barkan.

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 = 5:00, Master = 7:15, Expert = 14:30

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. More Cave puzzles can be found in The Art of Puzzles and in Roger Barkan’s Colossal Cave Collection.

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: Clue Symmetry and Logic

Author/Opus: This is the 58th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Tapa rules. Also, similar to Nurikabe, each clue cell is part of an island of horizontally and vertically connected white cells. Islands are allowed to touch diagonally. Islands may contain at most one clue cell, and the area of the island must be one of the numbers in the clue (as an example, if a clue is 15, then the island containing that clue must be either 1 cell or 5 cells large).

See also this example:

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 = 5:00, Master = 13:15, Expert = 26:30

Solution: PDF

Note: Follow this link for other Tapa variations and this link for classic Tapa. If you are new to this puzzle type, here are our easiest Tapa puzzles to get started on. More Tapa puzzles can be found in The Art of Puzzles and in Tapa and Variations, both by Serkan Yürekli.

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: Almost Antisymmetric

Author/Opus: This is the 21st puzzle from our contributing puzzlemaster Carl Worth.

Rules: Combination of Masyu and Balance Loop rules. In each horizontal row, all the circles obey the same rules, which are Masyu rules or Balance Loop rules. You must determine what rule applies to each row in order to form the single loop that solves the puzzle.

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 = 7:00, Master = 9:30, Expert = 19:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Masyu and Balance Loop puzzles.

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 letter entry mode.)

Theme: Just One (in Roman Numerals)

Author/Opus: This is the 20th puzzle from our contributing puzzlemaster Carl Worth.

Rules: Standard Pentominous rules.

Answer String: Enter the letter associated with the pentomino occupying each cell in the marked rows from left to right and in the marked columns from top to bottom, separating the groups with a comma. Use CAPITAL LETTERS!

Time Standards (highlight to view): Grandmaster = 5:45, Master = 7:45, Expert = 15:30

Solution: PDF

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

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: Just One

Author/Opus: This is the 145th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Tapa rules. The clue numbers refer to the groups of unshaded segments around that cell. Cells with numbers count as unshaded cells for adjacent clues. All other rules for the shaded Tapa are the same as usual.

Or see here:

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 = 4:15, Master = 6:45, Expert = 13:30

Solution: PDF; a solution video is available here.

Note: Follow this link for other Tapa variations and this link for classic Tapa. If you are new to this puzzle type, here are our easiest Tapa puzzles to get started on. More Tapa puzzles can be found in The Art of Puzzles and in Tapa and Variations, both by Serkan Yürekli.

(view directly for a larger image)

PDF

Example puzzle as 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 number entry mode.)

Theme: Logical

Author/Opus: This is the 18th puzzle from our newest contributing puzzlemaster Carl Worth.

Rules: (Hybrid of Fillomino and Snake Puzzles.) Divide the grid along the boundary lines so that every cell belongs to a snake. A snake is a one-cell-wide path at least two cells long that does not touch itself, not even diagonally. Circled cells must be at one of the ends of a snake. A snake may contain one circled cell, two circled cells, or no circled cells at all. Numbered cells must be part of a snake with a length of exactly that number of cells. A snake may contain one number, multiple identical numbers, or no numbers at all. Two snakes of the same length cannot touch each other horizontally or vertically.

Also see this example:

Answer String: For each cell in the marked rows/columns, enter the length of the snake it belongs to. Enter just the last digit for any two-digit number. This example has the key “35522,44462”.

Time Standards (highlight to view): Grandmaster = 11:30, Master = 22:00, Expert = 44:00

Solution: PDF

Note: Follow these link for other Fillomino or Snake puzzles.