PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between ship placement and shading modes. In ship placement mode, right click gives sea, left click gives circle/square, left click and drag for rounded ships.)

Theme: 2021 and 2022

Author/Opus: This is the 38th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Variation of standard Battleships rules. Instead of exterior clues, clues inside the grid indicate the number of adjacent squares, including diagonally adjacent squares, containing ship segments. Ships do not sit on cells with numbers. Use the indicated fleet.

Difficulty: 2 stars

Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:15, Expert = 4:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for classic Battleships and this link for Battleships variations. If you are new to this puzzle type, here are our easiest Battleships to get started on. More Battleships puzzles can be found in Battleships and Variations, in The Art of Puzzles, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

(This is a bonus “second” puzzle that is not connected to the usual Monday-Saturday week difficulty.)

PDF

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

Theme: Five Shurikens

Author/Opus: This is the 37th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard LITS rules.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 3:15, Master = 6:00, Expert = 12:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for more variations of LITS and this link for classic LITS. If you are new to this puzzle type, here are our easiest LITS to get started on. More LITS puzzles can be found in LOTS O’ LITS by Grant Fikes and Prasanna Seshadri, in The Art of Puzzles 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: Five Shurikens

Author/Opus: This is the 36th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Shade some cells black so that in each region there are exactly four unshaded cells that form an L, I, T, S, or O tetromino. When two unshaded tetrominoes share an edge across regions, they must not be the same shape regardless of rotations or reflections. All shaded cells must be connected into a single group, but no 2×2 group of cells can be entirely shaded black.

Example by Thomas Snyder:

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 12:00, Master = 25:00, Expert = 50:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for more variations of LITS and this link for classic LITS. If you are new to this puzzle type, here are our easiest LITS to get started on. More LITS puzzles can be found in LOTS O’ LITS by Grant Fikes and Prasanna Seshadri, in The Art of Puzzles 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; use tab to shift between shading mode and the linex mode where left click+drag draws lines and right click marks X’s)

Theme: Symmetric House

Author/Opus: This is the 35th puzzle from our contributing puzzlemaster JinHoo Ahn.

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:

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:15, Expert = 2:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for more Kuromasu puzzles.

PDF

(view directly for a larger image)

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

Theme: Square Dance

Author/Opus: This is the 34th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Star Battle rules. Three stars per row, column, and region.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 9:45, Master = 13:30, Expert = 27:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other classic Star Battles and this link for Star Battle variations. If you are new to this puzzle type, here are our easiest Star Battles to get started on. More Star Battle puzzles can be found in The Art of Puzzles, in the books Star Battle by JinHoo Ahn and Star Battle 2 by JinHoo Ahn and Murat Can Tonta, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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: Sequential Logic

Author/Opus: This is the 33rd puzzle from our contributing puzzlemaster JinHoo Ahn.

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:

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 8:30, Master = 14:15, Expert = 28:30

Solution: PDF; a solution video is also 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 to shift between number entry and shading modes.)

Theme: Magic Squares

Author/Opus: This is the 32nd puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place the digits in the indicated range (1-9) in some of the cells so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 7:15, Master = 20:00, Expert = 40:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

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: Evens

Author/Opus: This is the 31st puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Tapa rules.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:15, Expert = 2:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for classic Tapa and this link for Tapa variations. 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, in Tapa and Variations, and in our beginner-friendly collection Intro to GMPuzzles, all by Serkan Yürekli.

PDF

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

Theme: Antisymmetry

Author/Opus: This is the 30th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Arrow Sudoku rules. Also, standard Thermo-Sudoku rules.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:30, Master = 3:15, Expert = 6:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for more Arrow Sudoku. Follow this link for more Thermo-Sudoku puzzles. More Arrow and Thermo-Sudoku puzzles can be found in The Art of Sudoku 2.

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: Slanted Squares

Author/Opus: This is the 29th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Castle Wall rules.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 3:00, Expert = 6:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for more Castle Wall puzzles. If you are new to this puzzle type, here are our easiest Castle Wall puzzles to get started on. More Castle Wall puzzles can be found in our beginner-friendly collection Intro to GMPuzzles as well as the larger collection Castle Wall, both by Serkan Yürekli.