Solving Big Lines Puzzles: Work From the Edges In
A scanning routine for Hard and Expert Lines puzzles: start on the outline, peel inwards in waves, trace blocker chains when stuck, and use hints well.
Big Lines puzzles are solved from the edges in. Start on the outline of the shape, where the first free lines almost always sit with their arrows pointing out. Clear every free line you find, because any free line is safe, then scan the edge of the space you just opened. When nothing looks free, follow the chain of blockers from any line until you reach one with a clear lane. On Hard and Expert, a steady routine matters more than clever planning.
This guide is for players who are comfortable on Easy and Medium and want to finish Hard and Expert boards without tapping blocked lines. If you are new to the game, start with how to play Lines.
What changes from Easy to Expert
In Lines, the shape gets bigger at every level, and the lines get longer and more tangled. Each puzzle is a shape (a heart, a star, a circle, a diamond, a house or a square) packed with lines.
| Level | Shape size | What else changes |
|---|---|---|
| Easy | 11 squares across | Short lines, a large share free at the start |
| Medium | 15 squares across | Longer lines that turn more |
| Hard | 19 squares across | Long, winding lines; more lines waiting on each other |
| Expert | 23 squares across | The longest, most tangled lines; a small share free at the start and long chains of blockers |
The rule stays exactly the same at every level. A line slides out head first the way its arrow points, and only when nothing stands in front of its arrow all the way to the edge. What changes is how much there is to look at, and how many lines wait on other lines. On harder levels, the app deliberately places lines in each other's lanes, so a smaller share of the lines is free at the start and you work through longer chains.
That makes a big puzzle a search problem more than a deduction problem. Most of the work is finding the next free line on a crowded board.
Why the edges come first
At the start of a Lines puzzle, the shape is packed with lines, so almost every free line has its head on the outline and points out of the shape. A line deep inside has other lines in front of it in every direction, so in a full shape only a head on the outline, facing out, can see straight to the edge of the board.
There is one catch, and it is the heart. Near the top, its two rounded lobes face each other across the dip. A head on the inside edge of one lobe can point out across that gap and run straight into the other lobe. That line is blocked, even though it sits on the outline. So always follow the lane all the way to the edge of the board, not just to the edge of the shape.
Here is a small diamond to see the idea. It is much smaller than any real level.
Rows are numbered 1 to 7 from the top and columns 1 to 7 from the left. Five lines are free at the start:
- A points up from the top tip of the diamond.
- B points left from the left tip, and C points right from the right tip.
- D points down from the bottom tip.
- E points up from row 2, column 3. The square above it is outside the diamond, so nothing is in the way.
The four inner lines are all waiting. F points left into E. H points down into D. I points up into F and then A. G points right into H, I and C.
The sweep: a scanning routine for the first wave
The first wave of a big Lines puzzle goes fastest with a fixed routine: travel once round the whole outline and tap every free line you meet.
- Pick a starting point and a direction. For example, the top of the shape, going clockwise.
- At each head on the outline, ask one question: does the arrow point out of the shape, and is the lane clear all the way to the edge of the board?
- If yes, tap it straight away. Any free line is safe. You never need to save a line for later.
- Keep going until you are back where you started. Lines you freed along the way will be caught on the next pass.
Two habits save mistakes here. First, follow the arrow, not the body. A long line can wind along the outline while its head points inwards; only the head's direction counts. Second, check the whole lane. On a big board the arrow may cross a long empty stretch and still run into a line near the far edge.
The second wave: the edge of the space you opened
After the first sweep, the useful edge is no longer the outline of the shape. It is the border between the lines that are left and the empty squares you have cleared. Lines whose arrows point into that empty space are the likeliest to be free next.
On this board the second wave is F and H. Once F has gone, I's lane is clear; once H and I have gone, G can leave last. The whole board clears in four waves: A to E, then F and H, then I, then G.
On a real Expert board there are many more waves, but each one works the same way. Clear what is free, then look at the lines that border the new empty space. The puzzle peels away from the outside in, like an onion. The post on thinking in dependencies explains why these waves always exist, and why the order inside a wave never matters.
When nothing looks free: trace a chain
When a sweep finds nothing, stop scanning and trace one chain instead. Pick any line, follow its arrow to the first line in the way, then follow that line's arrow to the first line in its way, and so on. Lines never block each other in a circle, so the chain always ends at a line with a clear lane.
On the first diamond, starting from G: G's lane runs into H, and H's lane runs into D, which is free. Two hops.
Tracing on the board works better than planning in your head. Research on short-term memory suggests people can hold only about four chunks of information at once; Nelson Cowan's 2001 review describes a central capacity limit "averaging about four chunks" (Cowan, Behavioral and Brain Sciences, 2001). A chain on an Expert board can be longer than that. You do not need to remember it: just keep your eyes on the current line, hop, and tap when you reach the free end.
If you choose which chain to trace, start from a long, winding line. A long line covers many squares, so it sits in many other lanes. When it finally leaves, it often frees several lines at once.
Long, winding lines on Expert
Expert lines can snake across a large part of the shape, and they look much harder than they are. A winding line needs only one thing to leave: a clear lane in front of its head. The rest of its body follows the head out along that lane, so the body's twists do not matter for its own exit.
The twists matter for everyone else. Each square of a long line can sit in another line's lane, which is why one long line can hold up a whole region. So on Expert:
- Find the head first. Before thinking about a long line, locate its arrow. Ignore the body until you know where the head points.
- Ask what the long line needs. Its lane may hold only one or two lines. Clearing those can release a big chunk of the board.
- Expect a cascade. When a long line leaves, sweep the squares it covered. Lines whose arrows pointed across it may all be free now.
Staying calm on Expert
Expert Lines is a long look rather than a hard trick, so the main thing to manage is your attention. Nothing in Lines runs out. Your time is recorded, but no clock is pressing you, so you can stop and look for as long as you like.
- A blocked tap is not a disaster. It counts as a mistake and the puzzle carries on. The tapped line flashes red and nudges towards the line in its way, which is outlined in dashed red: that is a free first step of a chain trace.
- Undo is there. It brings back the last line you cleared, though hints and mistakes stay counted.
- Work in one direction at a time. If the board feels like noise, look only at arrows pointing up for a minute, checking each lane. Then right, then down, then left. A narrow question is easier to answer than "what can go?"
- Rest your eyes. On a board 23 squares across, a short pause often shows you a free line you looked past twice.
Using the hint well
A hint in Lines lights up one line that can go now. You get three free hints a day, so they are worth spending where they help most: after a full sweep and a chain trace have both failed, not at the first pause. A hint used that way teaches you something, because you can look at the lit line and ask why you missed it. Often it is a head you mistook for part of a body, or a lane you assumed was blocked without following it all the way.
Lines also has three power-ups beyond the hint. The Grid shows every line's way out until the next line leaves: green lanes are clear, red ones run into another line. The Hammer smashes any line you tap, even a blocked one. The Magnet pulls up to three lines out for you. They come from a shared stock that refills a little every day, and a solve that uses a hint or a power-up is marked as assisted rather than clean.
Frequently asked questions
How big is an Expert Lines puzzle?
An Expert shape is 23 squares across, compared with 19 on Hard, 15 on Medium and 11 on Easy. It is packed with lines, which are at their longest and most tangled on Expert.
Can I get stuck on a big Lines puzzle?
No. Lines only ever leave, so a free line stays free, and every Lines puzzle is built so that it can be cleared. If nothing looks free, a free line is there; trace a chain of blockers or use a hint to find it.
Does the order I clear lines in matter?
Only in one way: a line must wait for the lines in its lane. Among the lines that are free at any moment, the order makes no difference, so tap them in whatever order is easiest to see.
Why was my tap blocked when the line was on the edge?
On a heart, the lane may cross the dip between the two lobes and run into the other side. On any shape, a line may stand near the far end of the lane after a long empty stretch. Follow the arrow all the way to the edge of the board before you tap.
Your next Expert puzzle
Open an Expert puzzle on the Lines game page and run the routine: one clockwise sweep of the outline, then the edge of the space you opened, then a chain trace whenever you stall. Save the hint for when both have failed. If Expert still feels too much, play a few Hard boards with the same routine first. The Lines strategy guide covers more ways to spot the line that can go first, and arrow puzzles explained looks at why clearing a board feels so good. Every level in every game is compared in what changes at each puzzle level.