Quick steps to get started
Start from the marked cell: it is already filled and pulses. Without lifting your finger or the mouse button, draw the line through neighboring cells up, down, left or right. The goal is to fill every block on the board with a single line.
Made a mistake? Drag the line back to undo steps, or tap any cell of the line to continue from there. The Undo button removes the last step, and Restart begins the level again. If you get stuck, tap Hint and the game will show the next steps.
Special cells: a block with a ring must be crossed twice; a bridge is crossed once vertically and once horizontally, and you can't turn on it; an arrow can only be passed in its direction.
On a computer: arrows or WASD — step, Z or Backspace — undo, R — restart, H — hint, Esc — pause.
What's it all about?
Fill Line is a calm one-stroke logic puzzle. Start from the marked cell and draw one continuous line that fills every block on the board. You can't visit a cell twice, and there are no diagonal moves. It sounds simple, but the boards grow with every chapter and the solutions get trickier. The game has over 1,000 levels in 41 chapters. Each chapter has its own color theme, and the difficulty rises smoothly: easy breather levels alternate with hard ones, and a boss level waits at the end of every chapter. New mechanics appear along the way: double blocks you have to cross twice, bridges where the line crosses itself, and arrows that set the direction. A new daily puzzle with a reward opens every day. Spend coins to unlock themes, each with its own sound. There are no timers, no lives and no game over — just logic and the satisfying sound of filling cells.
Our player, ratings, and related picks
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Quick answers before you play
Platforms & genres
