Equinox Game

Equinox is a small logic puzzle with a memory twist. On the equinox, light and dark are equal, and so is every line of this grid: three full moons and three new moons in each row and each column. A small = between two cells means they hold the same moon, and a × means they differ. The signs show for a few seconds, then fade, so the logic has to live in your head, while the moons you place stay on the board to build on. The memory techniques on this site help you hold the signs.

How to play

1. Fill every cell of the 6 by 6 grid with a full moon or a new moon.
2. Each row and each column holds three full and three new moons.
3. No more than two of the same moon may sit next to each other in a row or a column.
4. A = between two cells means they hold the same moon. A × means they differ.
5. The signs and the given moons show for a short preview, then fade. The clock starts when they do. Your own moons always stay.
6. Tap a cell to cycle it: empty, full moon, new moon. Three alike in a line, or a fourth moon of one kind, is marked at once. A broken sign never is: you find out when the grid will not close.
7. Stuck? A peek brings every clue back for two seconds, and the clock keeps running. Press Space or PEEK.
8. Fill the last cell correctly and the clock stops. A full grid that is wrong only says "Not yet", and the clock runs on. Next puzzle deals a new grid at once, as many as you like. Change level goes back to the start.

Choose a level on the start screen. Easy has 9 given moons, 7 signs, a 10-second preview and three peeks, and its signs only turn faint. Normal, the default, has 5 given moons, 6 signs, an 8-second preview and two peeks, and leaves a dot where each sign was. Hard has 1 given moon, 7 signs, a 6-second preview and one peek, and everything fades, with a dashed ring where the given moon was. Every puzzle has exactly one solution. On a keyboard, move with the arrow keys, press Enter to cycle a cell, F for a full moon, N for a new moon, Backspace to clear and Space to peek. Escape pauses.

Scoring

Your score is your time, counted from the moment the signs fade. Each level keeps its own records:

• your best time,
• how many puzzles you have solved, and
• your longest run of puzzles solved without a peek.

Your records are saved in this browser only.

To hold a few signs at once, read about chunking and short-term memory. Or try our other free memory games.