Galaxies, Shikaku, and Queens all turn a square grid into a logic puzzle, but they ask for three different kinds of thinking. One puzzle is about rotationally symmetric regions around dots. Another is about rectangles whose areas match scattered numbers. The third is about placing a single queen in every row, column, and coloured region without two queens touching. They often sit near each other in a logic catalogue, yet each one needs its own listing, its own sample page, and its own answer key style.
This guide compares the three Puzzle Maker Pro modules so you can pick one interior for a KDP book, a classroom pack, or a printable bundle. It covers the rules in plain language, who each puzzle suits, the grid and difficulty controls you can actually set in the software, a side-by-side table, and two worked publishing scenarios with real page counts.
Three puzzle pages, three first impressions
When someone opens Look Inside, they should recognize the job immediately. Galaxies shows a lattice of dots. Shikaku shows numbers sitting in otherwise empty cells. Queens shows irregular coloured regions with no markers on the puzzle page at all. Mix those three looks under one title and the buyer does not know what they purchased.
The figure uses real puzzle data exported in Customer JSON form from Puzzle Maker Pro samples. It is not a screenshot of the desktop window. Your printed book will follow the same visual contract: puzzle page first, solution page second, with the answer drawn rather than typed into a single cell.
Galaxies — partition the grid around the dots
Galaxies (also searched as Tentai Show) seeds a rectangular grid with dots. The solver must cut the board into regions so that every cell belongs to exactly one region, every region contains exactly one dot, and each region is unchanged when rotated 180° about its dot. A dot can sit in a cell centre, on an edge between two cells, or on a corner where four cells meet, so the shapes are often less regular than they look from memory.
Who it suits. Teen and adult logic fans who already enjoy Nikoli-style region puzzles. The symmetry rule is visual and satisfying once it clicks. It is a weaker fit for very young children unless you switch dots to themed images (animals, holiday icons) and keep grids at the small end. Typical solve times run roughly 8–20 minutes on a 10×10 Normal board, longer on Unreasonable settings or larger grids.
Grid and difficulty in Puzzle Maker Pro. Rows and columns each run from 7 to 15; the default is 10×10. Difficulty is a two-step ladder only: Normal (deductive solving) and Unreasonable (may require backtracking). There is no separate Easy or Hard menu. You can replace solid dots with images from the built-in picker or your own files, optionally number the dots for teaching editions, and tune dot size for print. Quantity runs 1–1000 per generation pass; preview runs always produce a single puzzle.
Publishing notes. Page one should be dots on a clear grid. The answer key shows the symmetric regions with bold borders. If you use picture dots, say so in the description so parents know the mechanic is unchanged. Commercial rights for books you generate are covered by your Puzzle Maker Pro license as described on the homepage; that does not let you reprint someone else’s puzzle pages.
Shikaku — every number is a rectangle’s area
Shikaku prints numbers in selected cells. The solver divides the whole grid into non-overlapping rectangles. Each rectangle contains exactly one numbered clue, and that number equals the rectangle’s area in cells. A clue of 6 might be a 2×3 block or a 1×6 strip; only one placement completes the entire grid.
Who it suits. Upper elementary through adult audiences, especially teachers and parents who want logic with a clear arithmetic hook. Area reasoning makes Shikaku easy to justify in a math enrichment unit while still feeling like a proper puzzle book. Solve time scales with grid size and clue count: expect about 5–12 minutes on a 7×7 beginner page and 15–25 minutes on a dense 12×12 sheet.
Grid and difficulty in Puzzle Maker Pro. Rows and columns range from 4 to 20; the default is 7×7 with Lock to square turned on so width and height stay matched unless you deliberately unlock them. There is no difficulty dropdown. Instead, you control challenge with board size, the Larger areas slider (0.0–5.0, default 0.0), which biases the generator toward fewer, bigger rectangles, and Ensure unique solution (on by default), which rejects ambiguous boards. Puzzle display defaults to Numbers; you can switch to Patches, which replaces numeric clues with orientation glyphs—square, horizontal strip, or vertical strip—and that is a different buyer promise, so name it in the listing if you use it. Solution style can show region borders or coloured fills. Quantity per run is 1–100.
Publishing notes. Look Inside should show numbers on an empty grid, not a worksheet of arithmetic problems. The key shows rectangle borders (or fills). Use the product name Shikaku in titles and metadata; buyers do not search for the internal code name Rectangles.
Queens — place one queen per row, column, and region
Queens is not the classic chess puzzle where queens attack along full diagonals. Here the board is a square grid divided into irregular coloured regions. You place exactly one queen in every row, every column, and every region. Queens may not touch, including diagonally: the eight cells around a queen must stay empty. Two queens may sit on the same long diagonal if they are not adjacent.
Who it suits. Middle school through adult solvers who like placement logic with a strong visual cue from region colours. A 5×5 page is a friendly classroom warm-up; 7×7 and 8×8 pages feel like a serious logic magazine. Because the puzzle page hides the queens entirely, you must ship a solution section—buyers cannot check even one square from the problem page alone. Plan 6–15 minutes on 5×5 and 12–25 minutes on 8×8.
Grid and difficulty in Puzzle Maker Pro. The visible grid spinner runs 5×5 through 8×8; the default size on a fresh Creator session is 5×5. There is no difficulty combo box—challenge rises mainly with grid size and region complexity. The queen marker on the solution can be letters (default Q), numbers, colour shapes, or images; one symbol represents every queen on the board. Region fill colours are generated per puzzle. Quantity is 1–1000 per run.
Publishing notes. Titles and covers should say Queens, not chess n-Queens or Star Battle. Page one is coloured regions only. The key prints the queen markers. For a clean classroom PDF, turn region fills on and keep letters as the solution symbol so photocopies stay readable.
Side-by-side comparison
| Galaxies | Shikaku | Queens | |
|---|---|---|---|
| What the solver does | Partition cells into dot-symmetric regions | Slice the grid into rectangles matching clue areas | Place one queen per row, column, and region; no touching |
| Puzzle page looks like | Grid of black dots (or themed images) | Grid with scattered numbers (or patch glyphs) | Coloured irregular regions, empty of markers |
| Answer key looks like | Bold region borders around symmetric shapes | Rectangle borders or coloured blocks | Queen symbols on the solved grid |
| Default grid | 10×10 | 7×7 square | 5×5 |
| Grid range | 7–15 per side | 4–20 per side (square by default) | 5–8 per side |
| Difficulty controls | Normal vs Unreasonable | Board size, Larger areas, unique-solution toggle; optional Patches display | Mainly grid size (5–8) |
| Strong age band | Teens–adults (themed dots for younger) | Grades 3–12 and adults | Grades 4–12 and adults |
| Typical solve time | 8–20 min on 10×10 Normal | 5–25 min depending on size and clue density | 6–25 min from 5×5 to 8×8 |
| Module link | Galaxies | Shikaku | Queens |
Worked scenario 1 — 100-puzzle adult logic book on KDP
Goal. A single-type 8.5×11 paperback for experienced deductive solvers, sold as a dedicated Shikaku volume with honest difficulty branding.
Settings to generate. Open Shikaku, set Rows and Columns to 10 with Lock to square on. Leave Larger areas at 0.0 and Ensure unique solution on. Keep Puzzle display on Numbers and Solution style on Region borders. Generate 100 puzzles (four batches of 25, or Time Saver rows if you batch mixed sizes later).
Page math. Allow one puzzle per page at roughly 7.5×7.5 inches of play area, plus margins. That is 100 puzzle pages. Add a title page, a one-page how-to-play, and a table of contents (two pages once you list both puzzles and solutions). Put one solution per page so keys stay readable: another 100 pages. Total interior: about 205 pages before blank padding. At 15 minutes per puzzle, the book advertises roughly 25 hours of solving—credible for a mid-price logic title.
Recommendation. Choose Shikaku for this job. The number grid reads instantly in Look Inside, the unique-solution toggle backs a “one answer per puzzle” claim, and the arithmetic hook broadens Amazon browse categories without changing the mechanic. Galaxies would work for a symmetry-themed alternative series, but Shikaku’s clue density scales cleanly at 10×10. Queens would frustrate buyers who expected number rectangles because the empty region page looks like a different product.
Worked scenario 2 — 30-page classroom printable pack
Goal. A Teachers Pay Teachers or school-site download: short set, fast prints, minimal assembly, suitable for grades 4–6.
Settings to generate. Open Queens, set Grid size to 5×5. In Symbols, choose Letters with Q as the marker. Leave region fill colours on so each region is obvious on greyscale copiers. Generate 12 puzzles (quantity 12).
Page math. Two pages of teacher notes and student instructions. Twelve puzzle pages. Twelve solution pages with queens shown. One optional credits or standards page. That is 27 pages, leaving three pages for a cover wrapper or duplicate instruction sheet in the PDF. Each puzzle should take most students 8–12 minutes, so the pack fills two standard class periods with discussion.
Recommendation. Choose Queens for this pack. Region colours communicate the third constraint (one per region) without a long rules lecture, and 5×5 keeps forced moves common enough that students succeed. Shikaku 7×7 would suit a math enrichment unit but needs a tighter how-to-play because area reasoning takes longer to teach. Galaxies at 7×7 Normal is viable for a club session but expect more teacher coaching on edge and corner dots; save it for a follow-up volume once students trust logic grids.
Look Inside and single-type listings
Each module has a distinct puzzle page and answer key, as summarized in the table. The Look Inside article explains how the first pages prove difficulty and promise a key. For all three puzzles here, show an unsolved puzzle at print size, match the grid size your title advertises, and point to where solutions start.
Keep one mechanic per KDP title unless the cover explicitly sells a collection. Mixed interiors belong in honestly labelled variety books; see when not to mix puzzle types and mixed puzzle books if that is your plan. Channel-specific sizing for logic worksheets on Etsy or Teachers Pay Teachers lives in the Etsy logic printables and TPT logic worksheets guides; the chooser above still applies to which mechanic you export.
Other puzzles you might like
If your buyers want line-drawing logic instead of region splitting, read Slitherlink vs Numberlink vs Train Tracks for three puzzles built around paths and loops. For a wider logic shelf map on Amazon, logic puzzle books for KDP places these modules among other deduction types. Ready to try generation before you commit to a title? Getting started with Queens walks the Queens Creator settings step by step.