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 shading mode.)

Theme: Double Ring

Author/Opus: This is the 392nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Variation of Spiral Galaxies. In addition to the standard rules, some circles are shaded gray and must belong to galaxies containing two gray circles, not one, with the circles in rotationally symmetric spots for those galaxies.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 7:00, Master = 13:15, Expert = 26:30

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

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

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 shading mode.)

Author/Opus: This is the 84th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Spiral Galaxies rules. Also, there may not be four consecutive cells that are part of a galaxy in any row or column.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 4:00, Master = 6:30, Expert = 13:00

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

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

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 shading mode.)

Author/Opus: This is the 1st puzzle from guest contributor Jeffrey Jin.

Rules: Standard Spiral Galaxies rules.

Difficulty: 2.5 stars

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

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

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

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 shading mode.)

Theme: White Hole

Author/Opus: This is the 207th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Spiral Galaxies rules.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 1:45, Master = 2:45, Expert = 5:30

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

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

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 shading mode.)

Theme: Down the Middle

Author/Opus: This is the 353rd puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Spiral Galaxies rules.

Difficulty: 2 stars

Time Standards (highlight to view): Grandmaster = 1:00, Master = 2:30, Expert = 5:00

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

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

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 shading mode.)

Theme: Triplets

Author/Opus: This is the 78th puzzle from our contributing puzzlemaster Ashish Kumar.

Rules: Standard Spiral Galaxies rules.

Difficulty: 1.5 stars

Time Standards (highlight to view): Grandmaster = 0:50, Master = 1:20, Expert = 2:40

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

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

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: Box in Box

Author/Opus: This is the 8th puzzle from guest contributor Takeya Saikachi.

Rules: Variation of Pentominous rules. Divide the grid into 20 pentominoes so that no two pentominoes of the same shape (including rotations/reflections) share an edge. Each number in this grid represents a clue for a different letter/pentomino as in a regular Pentominous puzzle; all instances of a number must represent the same letter. An inventory of possible pentominoes is given below the puzzle.

Difficulty: 3 stars

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

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

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 linex mode where left click+drag draws lines and right click marks X’s)

Theme: Noah’s Ark

Author/Opus: This is the 9th puzzle from guest contributor Roger Barkan.

Rules: Standard Cave rules.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 5:45, Master = 9:15, Expert = 18:30

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

Note: Follow this link for classic Caves and this link for Cave variations. 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 Roger Barkan’s Colossal Cave Collection, in The Art of Puzzles, 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: Sevens

Author/Opus: This is the 7th puzzle from guest contributor Michael Tang.

Rules: Standard Cave rules.

Difficulty: 3 stars

Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:15, Expert = 8:30

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

Note: Follow this link for classic Caves and this link for Cave variations. 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 Roger Barkan’s Colossal Cave Collection, in The Art of Puzzles, 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: Mirror Cave

Author/Opus: This is the 386th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Cave rules.

Difficulty: 3 stars

Time Standards (highlight to view): Grandmaster = 2:45, Master = 4:15, Expert = 8:30

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

Note: Follow this link for classic Caves and this link for Cave variations. 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 Roger Barkan’s Colossal Cave Collection, in The Art of Puzzles, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.