Connect the dots and fill every cell. Link Lines is a free pipe puzzle. Connect the dots of matching colours with winding pipes that fill the whole grid, on 5x5 up to 8x8 boards.
How to play
The board is a square grid with pairs of same-coloured dots. Press on a dot and drag to draw a pipe through neighbouring cells until you reach the matching dot. Pipes move up, down, left and right only, never diagonally, and they can’t cross each other.
You solve a puzzle when two things are true: every pair is connected and every cell is covered by a pipe. If all the pairs are linked but some cells are still empty, the game reminds you with “Fill every cell!” and you have to reroute something.
Editing your pipes
- Drag back over your own pipe to shorten it.
- Draw through another colour’s pipe and you cut it at that point. The part before the cut stays, the rest is removed.
- You can’t enter a cell that holds a dot of a different colour.
- Press on a dot to restart that colour’s pipe from scratch, or press on any cell of a pipe to continue it from there.
Scoring
The counter at the top shows your moves. A move is starting a drag on a different colour from the one you drew last, so staying on one pipe and fixing it costs nothing extra. Underneath you’ll see Pipes (how many pairs are connected) and Fill (the percentage of cells covered).
Every solved puzzle adds one to your streak for the session, and the streak is your score. Your best is the most puzzles you solved in one sitting, and it starts over when you reload the page. Pick a grid size from 5×5 to 8×8 before you start; the default is 6×6. Each puzzle is freshly generated, so there is always at least one way to solve it.
Tips
- Start with the awkward dots. Dots in corners and on edges have the fewest options, so route those first.
- Watch for dead-end cells. If an empty cell has only one free neighbour, a pipe has to run through it, which tells you where that pipe goes.
- Hug the walls. Pipes that follow the edge leave the middle open for the others and stop empty pockets forming.
- Don’t be afraid to cut. Cutting a pipe is the quickest way to try a different route, and the dots are always there to start it again.
Why it’s fun
Link Lines is a calm puzzle you can finish in a couple of minutes, with satisfying pops and sounds as each pair connects and a burst of confetti when the whole board is full. Every pipe has its own colour and its own marker shape inside the dot, so it stays readable for colour-blind players too.