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: Black Box

Author/Opus: This is the 57th 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 = 3:45, Expert = 7:30

Solution: PDF and solving video.

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.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing, a letter entry mode, and a shading mode.)

Theme: 4 Pairs of Clues

Author/Opus: This is the 56th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Pentominous rules.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:15, Master = 4:00, Expert = 8:00

Solution: PDF and solving video.

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. More Pentominous puzzles can be found in the Plenty o’ Pentominous series by Grant Fikes 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; 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)

Theme: Winding Road

Author/Opus: This is the 54th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Sudoku rules.

Difficulty: 2.5 stars

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

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: 0 to 7

Author/Opus: This is the 53rd puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place a number from 0 to 9 into each area so that no two areas that touch orthogonally share the same number. Wherever four areas meet at a point (marked with dots as a visual aid), the numbers in those areas must add up to 10.

Also, see this example:

Difficulty: 2 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 other less common Number Placement puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools. Use left click to place mine, right click (in cell) to mark unused, right click (on edge/corner) to mark a note; hitting tab will also enable a shading mode. If you want more solving options, turn off Penpa-Lite option.)

Theme: Sequence Snakes

Author/Opus: This is the 52nd puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Minesweeper rules.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:50, Master = 1:15, Expert = 2:30

Solution: PDF and solving video.

Note: Follow this link for classic Minesweeper puzzles on this website and this link for variations on Minesweeper puzzles. If you are new to this puzzle type, here are our easiest Minesweeper Puzzles to get started on. More Minesweeper puzzles can be found in The Art of Puzzles 2.

PDF

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

Theme: Number Snakes

Author/Opus: This is the 51st puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Variation of Nurikabe. Shade some of the numbered cells so that the grid is divided into white regions, with each cell in such a region containing a number identical to the area of the region. Two white regions may only touch diagonally. All shaded cells must be connected with each other, but no 2×2 group of cells can be entirely shaded black.

Difficulty: 2 stars

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

Solution: PDF and solving video.

Note: Follow this link for classic Nurikabe and this link for Nurikabe variations. If you are new to this puzzle type, here are our easiest Nurikabe puzzles to get started on. More Nurikabe puzzles can be in The Art of Puzzles, in our beginner-friendly book Logic Puzzles 101, and in the e-book Nurikabe by Ashish Kumar.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: High Five

Author/Opus: This is the 50th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place the numbers in the indicated range (1-5) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number groups in that row or column, in order. Each sum is separated by at least one unused cell. A ? can represent any sum of 1 or larger.

Difficulty: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:00, Expert = 2:00

Solution: PDF and solving video.

Note: Follow this link for other Japanese Sums 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 number entry mode.)

Theme: 234

Author/Opus: This is the 49th puzzle from our contributing puzzlemaster JinHoo Ahn.

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:

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:00, Master = 1:40, Expert = 3:20

Solution: PDF and solving video.

Note: Follow this link for more Snake Pit puzzles. Follow these links for other Fillomino or Snake puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; in composite Star Battle mode a left click places a star, right click in a cell marks off the cell, and a right click on an edge or vertex marks in a dot as a placement note.)

Theme: Parallelograms

Author/Opus: This is the 48th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Fill some cells with stars so that each row (in a horizontal or either of two diagonal directions) and bold region contains the indicated number of stars. Stars cannot be placed in adjacent cells that share an edge.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:50, Master = 1:30, Expert = 3:00

Solution: PDF and solving video.

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 collections Intro to GMPuzzles by Serkan Yürekli and Starter Pack 5: Star Battle by JinHoo Ahn.