Gooby
Thread: join the dots, fill every square
A connect-the-dots logic puzzle in the Flow and Numberlink tradition. Draw a line between each pair of matching dots; lines never cross, and together they cover the whole board. 1,200 puzzles from 5×5 to 11×11, every one solvable by logic, no ads and no sign-up.
How to play Thread
- Draw a line between the two dots of each colour.
- Lines run square to square — never diagonally — and never cross or branch.
- Fill every square to finish. Fewer moves earn more stars.
Controls
- Drag from a dot to draw its line; drag from any square of a line to carry on from there or pull it back.
- Tap a dot to clear its line. Crossing another line cuts it back when you lift your finger.
Thread strategy
1. Only way
Corners and edges first: a square with just as many open sides as lines it needs must use all of them. Dots in corners often have only one way out.
2. One colour
Trace where each colour can still travel. A square that only one colour can reach from both of its dots belongs to that colour.
3. Bottleneck
When every route between two dots squeezes through one square, the line goes through it.
4. What if
On the big boards, suppose a line's end turns one way and follow the board on. If a square gets cut off or a colour can't reach its partner, it turns the other way.
Boards and difficulty
| Tier | Board | What it takes |
|---|---|---|
| Easy | 5×5 – 6×6 | Only one way to go |
| Medium | 7×7 | Longer lines |
| Hard | 8×8 | Bottlenecks |
| Expert | 9×9 | A what-if or two |
| Master | 10×10 | Chains of what-ifs |
| Extreme | 11×11 | Long winding lines |
Difficulty adapts to you: every finished puzzle updates your rating and the next one is picked around it.
Thread questions
Is Thread like Flow Free?
It's the same kind of puzzle — join matching dots with lines that don't cross and fill the whole board, also known as Numberlink. Thread is Gooby's free version with 1,200 puzzles, and every board has exactly one solution that logic can find.
Do I have to fill every square?
Yes. A board is finished when every pair is joined and every square is covered by a line.
How are stars counted?
A move is picking up a colour different from the last one you drew. Three stars need no hints, about one move per colour, and a time within par.
Is there a daily limit?
No. There are 1,200 puzzles and you can play as many as you like, whenever you like, for free.
Can I play Thread offline?
Yes. After the first visit it works with no connection. Add it to your home screen to use it like an app — here's how.
Flow Free is a trademark of Big Duck Games. Gooby is not affiliated with Big Duck Games.