Galaxies Puzzle
one dot per galaxy ยท same after a half turn

Play Galaxies โ€” Symmetry Logic Puzzle

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Tap a dot to pick its colourDrag to paint squaresRight-click clears

How to play Galaxies

Galaxies is a puzzle about symmetry. The grid is sprinkled with dots โ€” some in the middle of a square, some on a line between two squares, some on a corner where four squares meet.

Split the whole grid into galaxies so that each galaxy has exactly one dot, and spinning it half a turn around that dot gives exactly the same shape.

Every square has a partner on the other side of its dot. That one idea โ€” if this square is in, so is its mirror โ€” solves the whole puzzle.

How to play Galaxies

Split the grid into galaxies, each holding one dot and looking the same after a half turn around it.

The rules

  1. Every square must belong to exactly one galaxy.
  2. Each galaxy contains exactly one dot.
  3. Each galaxy has rotational symmetry around its dot: turn it 180ยฐ around the dot and it lands exactly on itself.
  4. Galaxies are joined pieces โ€” no galaxy is split in two.

Playing here

  1. Choose a size, how big the galaxies are and a difficulty, then press New Puzzle.
  2. Tap a dot to pick its colour, then tap or drag across squares to paint them. Auto-mirror paints the matching square on the other side of the dot for you.
  3. Tap a painted square again to clear it, or use Erase. Finished galaxies light up and their dot turns gold.
  4. Hint explains which dot must own the next square and why.

Tips

The full guide, with a worked example and common mistakes: How to play Galaxies.

Questions

Do galaxies have to look like spirals?

No โ€” any shape works as long as it looks the same after a half turn around its dot. Many are rectangles, crosses or zig-zags.

What does auto-mirror do?

When you paint a square, the matching square on the opposite side of the dot is painted too.

Is there always one answer?

Yes โ€” every puzzle here is checked to have exactly one way to split the grid.

How do I solve one from a book?

Open the Galaxies Solver, click where the dots are and press Solve.

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