One Line Fill: Brain Puzzle
Connect Squares Logic Game
Free
One line fill puzzle! Connect every block with a cute caterpillar. Brain teaser
A one line fill puzzle with a cute caterpillar! Draw a single path through every square, fill the whole grid, and munch every leaf on the way to the warp tile. Easy rules, real logic: a relaxing brain teaser and brain training game for quick breaks.
You can't visit the same square twice, so plan your route like a maze and enjoy the moment the path finally clicks.
■ How to Play
- Tap or drag to move the caterpillar across the grid
- Eat the leaf on every square to fill the board
- One stroke rule: no square can be visited twice
- Drag back over your trail to rewind, even all the way to the start, and retry freely
- Eat every leaf, then reach the warp tile to clear the stage
■ 2,000 Stages on One Path
- Clear a stage and go straight to the next one
- Boards grow from 3×4 up to 8×9 as the fill puzzles get deeper
- No lives and no time limit: play at your own pace
■ Beginner to Expert, Step by Step
You start on a tiny 3×4 board where thinking a few moves ahead is enough, even if you're new to puzzles. The grid then grows to 4×5, 5×6, 6×7, 7×8 and finally 8×9. More squares mean more possible paths, and simple line puzzles turn into real logic puzzles. Beginners get a light brain teaser, while experienced puzzlers get a genuine challenge.
■ Tips
- Build your route from the corners and edges to avoid dead ends
- Visit squares that could become dead ends early
- Keep a path open to the warp tile for the final moves
- Stuck? A hint shows you the correct route
■ How to Solve One Line Puzzles
One stroke puzzles reward logic, not luck. Start with the corners and with squares that have few open neighbors: with only one or two ways in and out, their order is almost fixed, and those forced moves reveal the shape of the whole path. Next, make sure no square is left stranded behind the caterpillar, because a walled-off square can never be reached again. Finally, work backward from the warp tile and decide the last few moves first. Thinking ahead like this makes a relaxed daily brain workout.
■ Features
- A cute caterpillar (worm) character with calm, cozy visuals
- One line, line fill, block fill and path puzzles in one game
- Logic puzzles built on the Hamiltonian path
- Portrait mode with simple tap and drag controls
- Background music can be switched on or off, handy in quiet places
- Free to play
■ Great Ways to Play
- Five minutes of brain training before bed or with your morning coffee
- A time killer on your commute or while you wait
■ FAQ
Q. What is a one line puzzle?
A. You connect every square on the board with a single line, never passing through the same square twice. It's also known as a one stroke puzzle or one touch drawing.
Q. What if I get stuck?
A. A hint reveals the correct route on the board step by step. Hints are limited, and you can get more by watching an ad.
Q. I'm not good at puzzles. Can I still play?
A. Yes. Stages start on small 3×4 boards, with no lives and no time limit, so you can retry as often as you like.
Q. How many stages are there?
A. 2,000. Each clear takes you to the next stage, and the board slowly grows.
Q. How is this different from other line or connect puzzles?
A. Unlike games where you connect dots of the same color or trace the edges of a shape, this is a fill-type one line puzzle: one path fills every square on the board. A perfect fit if you love grid fill puzzles.
■ Perfect For
- Fans of one line games, connect games and fill puzzles
- Adults who want daily brain training or a quick brain teaser
- Players who love mazes, logic puzzles and thinking games
- Anyone looking for a casual time killer with simple, easy rules
Munch every leaf and reach the warp tile. Can you clear all 2,000 one line puzzles?
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Fixed minor bugs and improved overall stability.
The developer, Gentak Works, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
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Information
- Seller
- Gentak Works
- Size
- 112.2 MB
- Category
- Puzzle
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPad
Requires iPadOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Contains
Advertising
- Copyright
- © 2026 Gentak Works