WPC Object Placement Mini-Playoff 1/3: Star Battle by JinHoo Ahn

The 30th World Puzzle Championship had five “mini-playoffs” to determine the top solvers in five different genres. Today we’ll be releasing the Object Placement puzzles starting with this “PLAYOFF” Star Battle puzzle by JinHoo Ahn.

Star Battle by JinHoo Ahn

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 corner marks in a dot as a placement note.)

Author/Opus: This is the 83rd puzzle from our contributing puzzlemaster JinHoo Ahn.

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

Estimated Difficulty: 2 stars

Solution: PDF for all Object Placement playoff puzzles.

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 these books in our e-store.

Snake Pit X by JinHoo Ahn

Snake Pit X by JinHoo Ahn

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: 2×3 Boxes

Author/Opus: This is the 66th 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. Cells with an X cannot be an end of a snake.

Also see this example:

Snake Pit

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 more Snake Pit puzzles. Follow these links for other Fillomino or Snake puzzles.

Star Battle by JinHoo Ahn

Star Battle by JinHoo Ahn

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 corner marks in a dot as a placement note.)

Theme: Diagonal Borders

Author/Opus: This is the 65th puzzle from our contributing puzzlemaster JinHoo Ahn.

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

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 1:40, Master = 3:30, Expert = 7:00

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.

Nanro (Tapa) by JinHoo Ahn

Nanro (Tapa) by JinHoo Ahn

PDF

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

Theme: Four by Four

Author/Opus: This is the 64th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Variation of Nanro rules with Tapa clue elements: Label some cells with numbers to form a single connected group of labeled cells; no 2×2 group of cells may be fully labeled. Each bold region must contain at least one labeled cell. Each number must equal the total count of labeled cells in that region. Numbers in a gray cell indicate the length of consecutive labeled cells in its neighbors. If there is more than one number in a gray cell, then there must be at least one white (not labeled) cell between the labeled cell groups. When two numbers are orthogonally adjacent across a region boundary, the numbers must be different.

Also see this example:

Nanro (Tapa) Example by Serkan Yürekli

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 9:00, Master = 13:00, Expert = 26:00

Solution: PDF and solving video.

Note: Follow this link for Nanro puzzles on this website and this link for variations on Nanro puzzles. If you are new to this puzzle type, here are our easiest Nanro Puzzles to get started on. More Nanro puzzles can be found in A Number o’ Nanro by Prasanna Seshadri.

Sudoku by JinHoo Ahn

Sudoku by JinHoo Ahn

PDF

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

Theme: Consecutive Dominoes

Author/Opus: This is the 63rd puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Sudoku rules.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:30, Expert = 7:00

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.

Kuromasu by JinHoo Ahn

Kuromasu by JinHoo Ahn

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: Multiples of 3

Author/Opus: This is the 62nd 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:

Kuromasu by Thomas Snyder

Difficulty: 1 star

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 Kuromasu puzzles. More Kuromasu can be found in Grandmaster Puzzles Quarterly Vol. 3.

Yajilin by JinHoo Ahn

Yajilin by JinHoo Ahn

(view directly for a larger image)

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: Parallel Lines

Author/Opus: This is the 61st puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Yajilin rules.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 6:00, Master = 7:30, Expert = 15:00

Solution: PDF and solving video.

Note: Follow this link for classic Yajilin and this link for Yajilin variations. If you are new to this puzzle type, here are our easiest Yajilin to get started on. More Yajilin puzzles can be found in The Art of Puzzles 2, in Yajilin by Murat Can Tonta and Prasanna Seshadri, and in our beginner-friendly book Logic Puzzles 101.

Star Battle by JinHoo Ahn

Star Battle by JinHoo Ahn

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 corner marks in a dot as a placement note.)

Theme: Candy Canes

Author/Opus: This is the 60th puzzle from our contributing puzzlemaster JinHoo Ahn.

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

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:00, Expert = 6:00

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.

Statue Park (Hex) by JinHoo Ahn

Statue Park (Hex) by JinHoo Ahn

PDF

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

Theme: Triplets

Author/Opus: This is the 59th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Standard Statue Park rules (with a hexagonal grid). This puzzle uses a standard tetrohex set.

Difficulty: 2 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 2:45, Expert = 5:30

Solution: PDF and solving video.

Note: Follow this link for other classic Statue Park and this link for Statue Park variations. If you are new to this puzzle type, here are our easiest Statue Parks to get started on. More Statue Park puzzles can be found in the ebook Statue Park by Murat Can Tonta.

Easy as ABC (Not First) by JinHoo Ahn

Easy as ABC (Not First) by JinHoo Ahn

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a letter entry mode and a shading mode. CAPS LOCK is recommended for letter entry.)

Theme: Groups of Liars

Author/Opus: This is the 58th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Fill some empty cells with the letters A, B, C so that each row and column contains each letter exactly once. Some cells will remain blank. The letters outside the grid do NOT indicate the first letter seen from that direction.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 1:45, Master = 3:30, Expert = 7:00

Solution: PDF and solving video.

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