Cella · Free in your browser
Cella: Heyawake Puzzle
Fill cells inside divided rooms. Every puzzle has exactly one solution.
The rules
- Fill some cells.
- A room's number is exactly how many of its cells are filled. A room without a number can have any count.
- No two filled cells are adjacent, left, right, up or down. Corners are fine.
- The empty cells form one connected area.
- A straight run of empty cells never passes through more than two rooms.
How to play here
Tap a cell to fill it, tap again to clear it. Press and hold to mark it empty. Drag to mark a run.
Three ways to play
Campaign
Chapters that start gently and bring in one new idea at a time.
Daily puzzle
A new board every day, the same for everyone. Solve every one in a month and that month's trophy is yours.
Endless
Keep going as long as you like, in Easy, Medium, Hard and Expert.
About the game
Cella is a Heyawake puzzle — the name means "divided rooms" — for players who like unhurried, honest logic.
The grid is cut into rooms, and some rooms carry a number. That number is exactly how many of the room's cells you fill. Two filled cells never touch side by side. Everything you leave empty forms one single connected area — and no straight line of empty cells may run through more than two rooms. Tap a cell to fill it; press and hold to mark it empty.
One solution, every time
Every puzzle has exactly one solution, checked before it ships by a solver that only uses techniques a person can follow and explain. The hint button uses that same solver: it shows the next step the board allows, and tells you which idea it used.
Learn it by playing it
Heyawake's last rule is about neither a single cell nor a single room, and no sentence in a rulebook makes it obvious. The walkthrough hands you real positions and asks for the one square that follows, then shows you why. No board in it was made up — each is a genuine puzzle stopped at the moment the idea it teaches becomes the forced next move.
Three ways to play, all offline
- 12 campaign chapters, from gentle openings to genuine work
- A daily puzzle, the same one for every player worldwide, with a gentle Monday and a demanding Sunday
- Endless mode in four difficulties: Easy, Medium, Hard, Expert
Measured in months, not streaks
Fill in every day of a calendar month and the month earns its own trophy. There is no streak to lose: a day you missed can still be filled in from the archive, so a week away from the game costs you nothing.
Built to be pleasant
- Warm Material 3 design, light and dark, following your system colours
- Completely offline — no account, no sign-in, no network needed
- Boards shaped for a phone held in one hand
- No countdowns you did not ask for and no interruptions
27 languages supported. No account required. Pure logic.
Common questions
Is Cella free?
Yes. You can play here without paying and without an account. Ads keep the lights on.
Where is my progress saved?
In this browser, on this device. If you clear the site data, your progress goes with it. A free Solvarium account keeps it safe.
Does it work on a phone or tablet?
Yes. It runs in any current browser on phones, tablets and computers, and the board resizes to fit the screen.
Does every puzzle really have one solution?
Yes. Every board goes through a solver before it ships, and anything with more than one solution is thrown out.