One Line: Block Fill Puzzle

ONE LINE. EVERY SQUARE. JUST ONCE.

One Line is a calm logic puzzle you learn in seconds: draw a single line that passes through every square exactly once. Look ahead, find the way, and watch the board light up when it's done.

FOUR WAYS TO PLAY
• Daily puzzle: one new puzzle every day, the same for everyone. Keep your streak going and share your result.
• Saga: a journey across 35 lands on a rolling world map. Each chapter brings something new to learn, and 200 pictures wait to be drawn and collected in your album.
• Zen: no clock, no pressure, just hexagonal boards to unwind with.
• Endless: race the clock. Every solved board buys you more time. How long can your run last?

THE BOARD TEACHES YOU
No long tutorials. New squares appear as you play, and each one is explained right on the board:
• Numbers that wait for a certain step of the line
• Arrows that show which way the line leaves a square
• Keys and locks, portals and fences
• Straight tracks, bends and more

FAIR BY DESIGN
• Every board is built from its own solution, so none is impossible
• A move that breaks a rule is simply refused, never punished
• Undo at any time; when you're stuck, a hint lights up the next squares

MORE TO ENJOY
• World rankings for the daily streak, Saga, Zen and Endless (you can turn them off)
• Achievements and cloud save with Google Play Games
• Line styles: Neon, Ink, Comet and Stars
• Light and dark themes, 36 languages
• No internet needed to play

ONE LINE+
An optional membership with no ads, unlimited energy, 3 hints a day, every line style, the archive of past daily puzzles and a second daily puzzle. No ADS+ and the line styles are also sold as one-time purchases.

One line. Every square. Just once.