210 puzzles

One Line Puzzles with Free Backtracking

Backtracking lets you revise a route without throwing away the whole attempt. Move to the immediately preceding square to shorten your line, or use Undo. This collection includes every current board because the same reversible tracing rule applies throughout all rounds.

A practical way to approach these boards

When a pocket is left unreachable, review the order of your recent turns. Retract along the existing line until you can try a different connection. You cannot jump across an older visited square: only the immediately preceding square retracts the head.

Rules for every board

Move orthogonally from the circle, cover all active squares, and reach the diamond last. Backtracking and retries are free. When browser storage is available, the board below each level introduction shares saved progress with the trial.

LEVEL 01One Line Puzzle level 1 opening diagram: 6 active squares, circle at row 4, column 3, diamond at row 5, column 3Find your flow

6 active squares · 5 verified moves · 0 gaps inside occupied bounds

Play level →
LEVEL 02One Line Puzzle level 2 opening diagram: 12 active squares, circle at row 3, column 3, diamond at row 5, column 6A little room to think

12 active squares · 11 verified moves · 0 gaps inside occupied bounds

Play level →
LEVEL 03One Line Puzzle level 3 opening diagram: 16 active squares, circle at row 3, column 3, diamond at row 5, column 4Outside, then inside

16 active squares · 15 verified moves · 0 gaps inside occupied bounds

Play level →
LEVEL 04One Line Puzzle level 4 opening diagram: 22 active squares, circle at row 4, column 3, diamond at row 4, column 6Keep both sides connected

22 active squares · 21 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 05One Line Puzzle level 5 opening diagram: 26 active squares, circle at row 3, column 4, diamond at row 5, column 3Leave a way back

26 active squares · 25 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 06One Line Puzzle level 6 opening diagram: 28 active squares, circle at row 2, column 4, diamond at row 3, column 6Two ways across

28 active squares · 27 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 07One Line Puzzle level 7 opening diagram: 28 active squares, circle at row 3, column 3, diamond at row 4, column 7A narrow return

28 active squares · 27 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 08One Line Puzzle level 8 opening diagram: 28 active squares, circle at row 4, column 4, diamond at row 6, column 7Keep the bridge open

28 active squares · 27 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 09One Line Puzzle level 9 opening diagram: 28 active squares, circle at row 4, column 7, diamond at row 6, column 6Across the gap

28 active squares · 27 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 10One Line Puzzle level 10 opening diagram: 28 active squares, circle at row 5, column 5, diamond at row 2, column 3One last connection

28 active squares · 27 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 11One Line Puzzle level 11 opening diagram: 32 active squares, circle at row 5, column 3, diamond at row 4, column 5Thread the middle

32 active squares · 31 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 12One Line Puzzle level 12 opening diagram: 32 active squares, circle at row 5, column 3, diamond at row 6, column 7Three open corners

32 active squares · 31 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 13One Line Puzzle level 13 opening diagram: 32 active squares, circle at row 6, column 4, diamond at row 5, column 6Protect the crossing

32 active squares · 31 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 14One Line Puzzle level 14 opening diagram: 32 active squares, circle at row 4, column 3, diamond at row 6, column 4Turn before the pocket

32 active squares · 31 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 15One Line Puzzle level 15 opening diagram: 32 active squares, circle at row 4, column 3, diamond at row 6, column 4Room to return

32 active squares · 31 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 16One Line Puzzle level 16 opening diagram: 34 active squares, circle at row 4, column 6, diamond at row 7, column 4Side by side

34 active squares · 33 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 17One Line Puzzle level 17 opening diagram: 34 active squares, circle at row 3, column 4, diamond at row 2, column 2A winding passage

34 active squares · 33 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 18One Line Puzzle level 18 opening diagram: 34 active squares, circle at row 7, column 5, diamond at row 7, column 6Save the inner turn

34 active squares · 33 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 19One Line Puzzle level 19 opening diagram: 34 active squares, circle at row 2, column 3, diamond at row 5, column 5Through both halves

34 active squares · 33 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 20One Line Puzzle level 20 opening diagram: 34 active squares, circle at row 2, column 3, diamond at row 3, column 3Leave the gate open

34 active squares · 33 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 21One Line Puzzle level 21 opening diagram: 38 active squares, circle at row 4, column 4, diamond at row 6, column 7A wider crossing

38 active squares · 37 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 22One Line Puzzle level 22 opening diagram: 38 active squares, circle at row 4, column 5, diamond at row 7, column 3Loops and links

38 active squares · 37 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 23One Line Puzzle level 23 opening diagram: 38 active squares, circle at row 2, column 7, diamond at row 4, column 4Reach the far corner

38 active squares · 37 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 24One Line Puzzle level 24 opening diagram: 38 active squares, circle at row 4, column 7, diamond at row 3, column 5Before the last turn

38 active squares · 37 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 25One Line Puzzle level 25 opening diagram: 38 active squares, circle at row 4, column 5, diamond at row 2, column 2A path between rooms

38 active squares · 37 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 26One Line Puzzle level 26 opening diagram: 40 active squares, circle at row 7, column 6, diamond at row 4, column 6Plan the return

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 27One Line Puzzle level 27 opening diagram: 40 active squares, circle at row 5, column 4, diamond at row 5, column 5Across the whole board

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 28One Line Puzzle level 28 opening diagram: 40 active squares, circle at row 5, column 5, diamond at row 3, column 4The remaining pocket

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 29One Line Puzzle level 29 opening diagram: 40 active squares, circle at row 5, column 4, diamond at row 6, column 6Hold the connection

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 30One Line Puzzle level 30 opening diagram: 40 active squares, circle at row 3, column 7, diamond at row 2, column 7One continuous journey

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 31One Line Puzzle level 31 opening diagram: 40 active squares, circle at row 5, column 6, diamond at row 6, column 4Between the pockets

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 32One Line Puzzle level 32 opening diagram: 40 active squares, circle at row 4, column 2, diamond at row 3, column 4A crossing to keep

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 33One Line Puzzle level 33 opening diagram: 40 active squares, circle at row 3, column 8, diamond at row 5, column 7Both sides of the gap

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 34One Line Puzzle level 34 opening diagram: 40 active squares, circle at row 4, column 6, diamond at row 3, column 4Return through the middle

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 35One Line Puzzle level 35 opening diagram: 40 active squares, circle at row 4, column 5, diamond at row 5, column 7One open passage

40 active squares · 39 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 36One Line Puzzle level 36 opening diagram: 42 active squares, circle at row 8, column 4, diamond at row 7, column 6Seven missing squares

42 active squares · 41 verified moves · 7 gaps inside occupied bounds

Play level →
LEVEL 37One Line Puzzle level 37 opening diagram: 42 active squares, circle at row 3, column 7, diamond at row 5, column 6Connections through the middle

42 active squares · 41 verified moves · 7 gaps inside occupied bounds

Play level →
LEVEL 38One Line Puzzle level 38 opening diagram: 42 active squares, circle at row 7, column 3, diamond at row 4, column 5The inner connection

42 active squares · 41 verified moves · 7 gaps inside occupied bounds

Play level →
LEVEL 39One Line Puzzle level 39 opening diagram: 42 active squares, circle at row 4, column 2, diamond at row 3, column 8Keep room to turn

42 active squares · 41 verified moves · 7 gaps inside occupied bounds

Play level →
LEVEL 40One Line Puzzle level 40 opening diagram: 42 active squares, circle at row 6, column 7, diamond at row 4, column 4Links across the board

42 active squares · 41 verified moves · 7 gaps inside occupied bounds

Play level →
LEVEL 41One Line Puzzle level 41 opening diagram: 44 active squares, circle at row 7, column 3, diamond at row 5, column 4The far-side pocket

44 active squares · 43 verified moves · 5 gaps inside occupied bounds

Play level →
LEVEL 42One Line Puzzle level 42 opening diagram: 44 active squares, circle at row 6, column 7, diamond at row 8, column 8Thread two openings

44 active squares · 43 verified moves · 5 gaps inside occupied bounds

Play level →
LEVEL 43One Line Puzzle level 43 opening diagram: 44 active squares, circle at row 3, column 4, diamond at row 7, column 5Across the broken grid

44 active squares · 43 verified moves · 5 gaps inside occupied bounds

Play level →
LEVEL 44One Line Puzzle level 44 opening diagram: 44 active squares, circle at row 3, column 8, diamond at row 4, column 8A careful crossing

44 active squares · 43 verified moves · 5 gaps inside occupied bounds

Play level →
LEVEL 45One Line Puzzle level 45 opening diagram: 44 active squares, circle at row 4, column 8, diamond at row 7, column 6The last open corner

44 active squares · 43 verified moves · 5 gaps inside occupied bounds

Play level →
LEVEL 46One Line Puzzle level 46 opening diagram: 46 active squares, circle at row 3, column 7, diamond at row 8, column 7Space for a return

46 active squares · 45 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 47One Line Puzzle level 47 opening diagram: 46 active squares, circle at row 7, column 3, diamond at row 5, column 8The winding center

46 active squares · 45 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 48One Line Puzzle level 48 opening diagram: 46 active squares, circle at row 2, column 6, diamond at row 7, column 8Before the final stretch

46 active squares · 45 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 49One Line Puzzle level 49 opening diagram: 46 active squares, circle at row 6, column 3, diamond at row 3, column 3A narrow connection

46 active squares · 45 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 50One Line Puzzle level 50 opening diagram: 46 active squares, circle at row 7, column 7, diamond at row 7, column 8The other side

46 active squares · 45 verified moves · 3 gaps inside occupied bounds

Play level →
LEVEL 51One Line Puzzle level 51 opening diagram: 48 active squares, circle at row 4, column 6, diamond at row 4, column 5Eight islands

48 active squares · 47 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 52One Line Puzzle level 52 opening diagram: 48 active squares, circle at row 3, column 5, diamond at row 6, column 3Connect the outer rooms

48 active squares · 47 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 53One Line Puzzle level 53 opening diagram: 48 active squares, circle at row 7, column 6, diamond at row 8, column 2A turn between gaps

48 active squares · 47 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 54One Line Puzzle level 54 opening diagram: 48 active squares, circle at row 3, column 6, diamond at row 8, column 8Keep a way through

48 active squares · 47 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 55One Line Puzzle level 55 opening diagram: 48 active squares, circle at row 4, column 7, diamond at row 5, column 7Keep the regions connected

48 active squares · 47 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 56One Line Puzzle level 56 opening diagram: 50 active squares, circle at row 4, column 6, diamond at row 4, column 3Across the whole canvas

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 57One Line Puzzle level 57 opening diagram: 50 active squares, circle at row 8, column 5, diamond at row 5, column 5A path around six gaps

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 58One Line Puzzle level 58 opening diagram: 50 active squares, circle at row 5, column 5, diamond at row 8, column 7Hold the middle open

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 59One Line Puzzle level 59 opening diagram: 50 active squares, circle at row 6, column 3, diamond at row 3, column 5Leave no pocket behind

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 60One Line Puzzle level 60 opening diagram: 50 active squares, circle at row 7, column 8, diamond at row 7, column 3One line to the finish

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 61One Line Puzzle level 61 opening diagram: 50 active squares, circle at row 6, column 5, diamond at row 4, column 8Across both open edges

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 62One Line Puzzle level 62 opening diagram: 50 active squares, circle at row 7, column 2, diamond at row 6, column 6Leave the middle connected

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 63One Line Puzzle level 63 opening diagram: 50 active squares, circle at row 7, column 5, diamond at row 4, column 7An exit for each pocket

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 64One Line Puzzle level 64 opening diagram: 50 active squares, circle at row 7, column 4, diamond at row 2, column 4Around the broken border

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 65One Line Puzzle level 65 opening diagram: 50 active squares, circle at row 5, column 6, diamond at row 4, column 6Meet at the inner turn

50 active squares · 49 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 66One Line Puzzle level 66 opening diagram: 52 active squares, circle at row 8, column 6, diamond at row 8, column 7Three links to preserve

52 active squares · 51 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 67One Line Puzzle level 67 opening diagram: 52 active squares, circle at row 4, column 4, diamond at row 6, column 7Return beside the diamond

52 active squares · 51 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 68One Line Puzzle level 68 opening diagram: 52 active squares, circle at row 4, column 6, diamond at row 7, column 2The long outside passage

52 active squares · 51 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 69One Line Puzzle level 69 opening diagram: 52 active squares, circle at row 7, column 5, diamond at row 4, column 3Separate paths to connect

52 active squares · 51 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 70One Line Puzzle level 70 opening diagram: 52 active squares, circle at row 7, column 4, diamond at row 4, column 4One link still open

52 active squares · 51 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 71One Line Puzzle level 71 opening diagram: 54 active squares, circle at row 6, column 4, diamond at row 5, column 8Across the narrow middle

54 active squares · 53 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 72One Line Puzzle level 72 opening diagram: 54 active squares, circle at row 3, column 2, diamond at row 5, column 3Connections across the open regions

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 73One Line Puzzle level 73 opening diagram: 54 active squares, circle at row 3, column 1, diamond at row 3, column 8Keep the far edge free

54 active squares · 53 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 74One Line Puzzle level 74 opening diagram: 54 active squares, circle at row 6, column 6, diamond at row 2, column 5Keep the inner crossings open

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 75One Line Puzzle level 75 opening diagram: 54 active squares, circle at row 7, column 8, diamond at row 5, column 1Connect the last pocket

54 active squares · 53 verified moves · 2 gaps inside occupied bounds

Play level →
LEVEL 76One Line Puzzle level 76 opening diagram: 52 active squares, circle at row 5, column 6, diamond at row 7, column 7Eight rows to connect

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 77One Line Puzzle level 77 opening diagram: 52 active squares, circle at row 7, column 7, diamond at row 1, column 2A passage between islands

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 78One Line Puzzle level 78 opening diagram: 52 active squares, circle at row 7, column 2, diamond at row 2, column 6Both sides need an exit

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 79One Line Puzzle level 79 opening diagram: 52 active squares, circle at row 6, column 8, diamond at row 4, column 5Return through the open gap

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 80One Line Puzzle level 80 opening diagram: 52 active squares, circle at row 4, column 5, diamond at row 2, column 8Protect the central link

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 81One Line Puzzle level 81 opening diagram: 54 active squares, circle at row 7, column 5, diamond at row 2, column 5A route across the gaps

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 82One Line Puzzle level 82 opening diagram: 54 active squares, circle at row 4, column 4, diamond at row 5, column 2Leave a way around

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 83One Line Puzzle level 83 opening diagram: 54 active squares, circle at row 4, column 7, diamond at row 8, column 8The inner edge first

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 84One Line Puzzle level 84 opening diagram: 54 active squares, circle at row 3, column 7, diamond at row 8, column 5Follow the open border

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 85One Line Puzzle level 85 opening diagram: 54 active squares, circle at row 4, column 8, diamond at row 8, column 3A link to the far side

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 86One Line Puzzle level 86 opening diagram: 56 active squares, circle at row 8, column 2, diamond at row 4, column 5Across the widest board

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 87One Line Puzzle level 87 opening diagram: 56 active squares, circle at row 4, column 5, diamond at row 5, column 7Thread the last passages

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 88One Line Puzzle level 88 opening diagram: 56 active squares, circle at row 3, column 2, diamond at row 7, column 5Keep the diamond reachable

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 89One Line Puzzle level 89 opening diagram: 56 active squares, circle at row 7, column 5, diamond at row 3, column 2The final pocket to fill

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 90One Line Puzzle level 90 opening diagram: 56 active squares, circle at row 7, column 3, diamond at row 5, column 4One continuous return

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 91One Line Puzzle level 91 opening diagram: 52 active squares, circle at row 7, column 8, diamond at row 2, column 4Read the scattered spaces

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 92One Line Puzzle level 92 opening diagram: 52 active squares, circle at row 7, column 4, diamond at row 7, column 3Keep two passages open

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 93One Line Puzzle level 93 opening diagram: 52 active squares, circle at row 4, column 4, diamond at row 1, column 2Across the upper pocket

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 94One Line Puzzle level 94 opening diagram: 52 active squares, circle at row 2, column 5, diamond at row 7, column 5A link around the centre

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 95One Line Puzzle level 95 opening diagram: 52 active squares, circle at row 2, column 3, diamond at row 5, column 3Return beside the outer gap

52 active squares · 51 verified moves · 12 gaps inside occupied bounds

Play level →
LEVEL 96One Line Puzzle level 96 opening diagram: 54 active squares, circle at row 3, column 2, diamond at row 8, column 2An exit from each side

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 97One Line Puzzle level 97 opening diagram: 54 active squares, circle at row 7, column 3, diamond at row 6, column 5Join the divided edges

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 98One Line Puzzle level 98 opening diagram: 54 active squares, circle at row 6, column 2, diamond at row 3, column 6Through the middle passage

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 99One Line Puzzle level 99 opening diagram: 54 active squares, circle at row 2, column 5, diamond at row 5, column 3Leave the corner connected

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 100One Line Puzzle level 100 opening diagram: 54 active squares, circle at row 5, column 7, diamond at row 4, column 5Past the narrow opening

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 101One Line Puzzle level 101 opening diagram: 56 active squares, circle at row 2, column 7, diamond at row 4, column 6Weave around both spaces

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 102One Line Puzzle level 102 opening diagram: 56 active squares, circle at row 7, column 7, diamond at row 1, column 4The far edge still waits

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 103One Line Puzzle level 103 opening diagram: 56 active squares, circle at row 7, column 5, diamond at row 5, column 4An unfinished inner turn

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 104One Line Puzzle level 104 opening diagram: 56 active squares, circle at row 8, column 7, diamond at row 3, column 3Across the quiet border

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 105One Line Puzzle level 105 opening diagram: 56 active squares, circle at row 2, column 8, diamond at row 3, column 4Connect the remaining sides

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 106One Line Puzzle level 106 opening diagram: 54 active squares, circle at row 7, column 2, diamond at row 6, column 8A different way around

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 107One Line Puzzle level 107 opening diagram: 54 active squares, circle at row 2, column 3, diamond at row 6, column 6Two pockets to revisit

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 108One Line Puzzle level 108 opening diagram: 54 active squares, circle at row 6, column 4, diamond at row 1, column 2Cross the open centre

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 109One Line Puzzle level 109 opening diagram: 54 active squares, circle at row 2, column 6, diamond at row 4, column 3Keep the lower passage

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 110One Line Puzzle level 110 opening diagram: 54 active squares, circle at row 4, column 4, diamond at row 6, column 1Return across the upper edge

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 111One Line Puzzle level 111 opening diagram: 56 active squares, circle at row 1, column 3, diamond at row 5, column 2The route between gaps

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 112One Line Puzzle level 112 opening diagram: 56 active squares, circle at row 7, column 5, diamond at row 6, column 1Leave the inner door open

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 113One Line Puzzle level 113 opening diagram: 56 active squares, circle at row 5, column 1, diamond at row 7, column 4One more region to join

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 114One Line Puzzle level 114 opening diagram: 56 active squares, circle at row 6, column 6, diamond at row 6, column 5Around the final bend

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 115One Line Puzzle level 115 opening diagram: 56 active squares, circle at row 1, column 7, diamond at row 2, column 5Both edges need a link

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 116One Line Puzzle level 116 opening diagram: 58 active squares, circle at row 7, column 6, diamond at row 4, column 4Read the widest shape

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 117One Line Puzzle level 117 opening diagram: 58 active squares, circle at row 2, column 4, diamond at row 2, column 5An exit beyond the corner

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 118One Line Puzzle level 118 opening diagram: 58 active squares, circle at row 8, column 7, diamond at row 1, column 5Thread the outer connections

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 119One Line Puzzle level 119 opening diagram: 58 active squares, circle at row 3, column 1, diamond at row 1, column 4Keep one passage for last

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 120One Line Puzzle level 120 opening diagram: 58 active squares, circle at row 4, column 6, diamond at row 4, column 7A fourth continuous journey

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 121One Line Puzzle level 121 opening diagram: 54 active squares, circle at row 5, column 5, diamond at row 6, column 1Leave the inner passage

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 122One Line Puzzle level 122 opening diagram: 54 active squares, circle at row 2, column 4, diamond at row 4, column 3An open way to the centre

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 123One Line Puzzle level 123 opening diagram: 54 active squares, circle at row 2, column 6, diamond at row 6, column 3Return around the side pocket

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 124One Line Puzzle level 124 opening diagram: 54 active squares, circle at row 5, column 3, diamond at row 6, column 1The border still connects

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 125One Line Puzzle level 125 opening diagram: 54 active squares, circle at row 2, column 8, diamond at row 4, column 3Keep the inner square reachable

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 126One Line Puzzle level 126 opening diagram: 56 active squares, circle at row 8, column 4, diamond at row 2, column 1Between three open regions

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 127One Line Puzzle level 127 opening diagram: 56 active squares, circle at row 6, column 6, diamond at row 4, column 1Read the edge before crossing

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 128One Line Puzzle level 128 opening diagram: 56 active squares, circle at row 2, column 2, diamond at row 4, column 7A passage beneath the gap

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 129One Line Puzzle level 129 opening diagram: 56 active squares, circle at row 4, column 4, diamond at row 1, column 2Join the two far corners

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 130One Line Puzzle level 130 opening diagram: 56 active squares, circle at row 6, column 7, diamond at row 2, column 8Return through the middle

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 131One Line Puzzle level 131 opening diagram: 58 active squares, circle at row 7, column 6, diamond at row 4, column 6Along the wider border

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 132One Line Puzzle level 132 opening diagram: 58 active squares, circle at row 3, column 5, diamond at row 1, column 8Leave room for the last turn

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 133One Line Puzzle level 133 opening diagram: 58 active squares, circle at row 6, column 4, diamond at row 1, column 2Connect the farthest pocket

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 134One Line Puzzle level 134 opening diagram: 58 active squares, circle at row 3, column 4, diamond at row 6, column 6The open edge comes later

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 135One Line Puzzle level 135 opening diagram: 58 active squares, circle at row 8, column 7, diamond at row 8, column 4One region at a time

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 136One Line Puzzle level 136 opening diagram: 54 active squares, circle at row 6, column 6, diamond at row 8, column 5A new order through the gaps

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 137One Line Puzzle level 137 opening diagram: 54 active squares, circle at row 7, column 3, diamond at row 3, column 8Keep the short link open

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 138One Line Puzzle level 138 opening diagram: 54 active squares, circle at row 7, column 7, diamond at row 7, column 8Across the split middle

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 139One Line Puzzle level 139 opening diagram: 54 active squares, circle at row 5, column 4, diamond at row 6, column 4Return beside the narrow edge

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 140One Line Puzzle level 140 opening diagram: 54 active squares, circle at row 5, column 8, diamond at row 4, column 8The pocket beyond the bend

54 active squares · 53 verified moves · 10 gaps inside occupied bounds

Play level →
LEVEL 141One Line Puzzle level 141 opening diagram: 56 active squares, circle at row 4, column 5, diamond at row 4, column 8A path around the empty centre

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 142One Line Puzzle level 142 opening diagram: 56 active squares, circle at row 8, column 3, diamond at row 3, column 3Join both sides before leaving

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 143One Line Puzzle level 143 opening diagram: 56 active squares, circle at row 3, column 7, diamond at row 5, column 6Save the inner passage

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 144One Line Puzzle level 144 opening diagram: 56 active squares, circle at row 1, column 3, diamond at row 5, column 6The far corner needs a return

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 145One Line Puzzle level 145 opening diagram: 56 active squares, circle at row 5, column 4, diamond at row 3, column 3Connect the lower edge last

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 146One Line Puzzle level 146 opening diagram: 58 active squares, circle at row 6, column 4, diamond at row 6, column 5Through the final open regions

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 147One Line Puzzle level 147 opening diagram: 58 active squares, circle at row 4, column 5, diamond at row 7, column 7A return beside the diamond

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 148One Line Puzzle level 148 opening diagram: 58 active squares, circle at row 2, column 1, diamond at row 4, column 6Leave the last connection free

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 149One Line Puzzle level 149 opening diagram: 58 active squares, circle at row 7, column 2, diamond at row 1, column 5The fifth round takes shape

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 150One Line Puzzle level 150 opening diagram: 58 active squares, circle at row 8, column 2, diamond at row 5, column 6One line through every region

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 151One Line Puzzle level 151 opening diagram: 56 active squares, circle at row 6, column 1, diamond at row 8, column 4Keep the upper passage connected

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 152One Line Puzzle level 152 opening diagram: 56 active squares, circle at row 6, column 4, diamond at row 4, column 5A return around the small gap

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 153One Line Puzzle level 153 opening diagram: 56 active squares, circle at row 2, column 2, diamond at row 7, column 4The side region waits

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 154One Line Puzzle level 154 opening diagram: 56 active squares, circle at row 5, column 5, diamond at row 7, column 6Across the open square

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 155One Line Puzzle level 155 opening diagram: 56 active squares, circle at row 2, column 3, diamond at row 1, column 5Bring the edges together

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 156One Line Puzzle level 156 opening diagram: 58 active squares, circle at row 4, column 3, diamond at row 3, column 5Between the inward turns

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 157One Line Puzzle level 157 opening diagram: 58 active squares, circle at row 6, column 3, diamond at row 8, column 4Keep a route to the far side

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 158One Line Puzzle level 158 opening diagram: 58 active squares, circle at row 2, column 3, diamond at row 3, column 5The pocket beside the circle

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 159One Line Puzzle level 159 opening diagram: 58 active squares, circle at row 7, column 3, diamond at row 4, column 3Link the upper and lower regions

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 160One Line Puzzle level 160 opening diagram: 58 active squares, circle at row 4, column 4, diamond at row 3, column 6A passage through the centre

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 161One Line Puzzle level 161 opening diagram: 60 active squares, circle at row 1, column 3, diamond at row 5, column 4Read the nearly full board

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 162One Line Puzzle level 162 opening diagram: 60 active squares, circle at row 2, column 7, diamond at row 7, column 7An opening around four gaps

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 163One Line Puzzle level 163 opening diagram: 60 active squares, circle at row 7, column 2, diamond at row 4, column 4Leave the corner connected

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 164One Line Puzzle level 164 opening diagram: 60 active squares, circle at row 7, column 3, diamond at row 5, column 8The long way to the diamond

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 165One Line Puzzle level 165 opening diagram: 60 active squares, circle at row 1, column 6, diamond at row 4, column 8Return before closing the edge

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 166One Line Puzzle level 166 opening diagram: 56 active squares, circle at row 3, column 8, diamond at row 8, column 8New gaps along the border

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 167One Line Puzzle level 167 opening diagram: 56 active squares, circle at row 7, column 7, diamond at row 2, column 3Keep both exits available

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 168One Line Puzzle level 168 opening diagram: 56 active squares, circle at row 2, column 8, diamond at row 3, column 6Through the opposite region

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 169One Line Puzzle level 169 opening diagram: 56 active squares, circle at row 2, column 1, diamond at row 3, column 1Around the interrupted middle

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 170One Line Puzzle level 170 opening diagram: 56 active squares, circle at row 4, column 6, diamond at row 4, column 1The outer connection remains

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 171One Line Puzzle level 171 opening diagram: 58 active squares, circle at row 6, column 3, diamond at row 1, column 1Connect the narrow regions

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 172One Line Puzzle level 172 opening diagram: 58 active squares, circle at row 7, column 7, diamond at row 1, column 8A turn beside the last pocket

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 173One Line Puzzle level 173 opening diagram: 58 active squares, circle at row 6, column 4, diamond at row 1, column 8Leave a link across the board

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 174One Line Puzzle level 174 opening diagram: 58 active squares, circle at row 7, column 7, diamond at row 8, column 7The centre connects both sides

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 175One Line Puzzle level 175 opening diagram: 58 active squares, circle at row 4, column 3, diamond at row 4, column 4Reach the far edge and return

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 176One Line Puzzle level 176 opening diagram: 60 active squares, circle at row 7, column 7, diamond at row 5, column 4Across the final four gaps

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 177One Line Puzzle level 177 opening diagram: 60 active squares, circle at row 4, column 6, diamond at row 5, column 6Keep the inward passage open

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 178One Line Puzzle level 178 opening diagram: 60 active squares, circle at row 5, column 2, diamond at row 5, column 3One last return to the border

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 179One Line Puzzle level 179 opening diagram: 60 active squares, circle at row 4, column 1, diamond at row 8, column 2The sixth round comes together

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 180One Line Puzzle level 180 opening diagram: 60 active squares, circle at row 4, column 4, diamond at row 5, column 4Every region in one line

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 181One Line Puzzle level 181 opening diagram: 58 active squares, circle at row 2, column 4, diamond at row 5, column 8A new order through the open board

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 182One Line Puzzle level 182 opening diagram: 58 active squares, circle at row 3, column 1, diamond at row 2, column 3Keep a way around the inner gap

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 183One Line Puzzle level 183 opening diagram: 58 active squares, circle at row 3, column 3, diamond at row 3, column 6The far region stays connected

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 184One Line Puzzle level 184 opening diagram: 58 active squares, circle at row 7, column 3, diamond at row 3, column 6Join the borders before the finish

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 185One Line Puzzle level 185 opening diagram: 58 active squares, circle at row 1, column 4, diamond at row 2, column 6Return between the open edges

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 186One Line Puzzle level 186 opening diagram: 56 active squares, circle at row 7, column 5, diamond at row 8, column 5Read the breaks in the grid

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 187One Line Puzzle level 187 opening diagram: 56 active squares, circle at row 1, column 7, diamond at row 1, column 8Leave both regions reachable

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 188One Line Puzzle level 188 opening diagram: 56 active squares, circle at row 8, column 2, diamond at row 7, column 2Across the border and back

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 189One Line Puzzle level 189 opening diagram: 56 active squares, circle at row 1, column 2, diamond at row 8, column 4Keep the small pocket open

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 190One Line Puzzle level 190 opening diagram: 56 active squares, circle at row 7, column 2, diamond at row 3, column 5A route between the gaps

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 191One Line Puzzle level 191 opening diagram: 60 active squares, circle at row 2, column 7, diamond at row 6, column 6Four gaps and a longer line

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 192One Line Puzzle level 192 opening diagram: 60 active squares, circle at row 1, column 4, diamond at row 5, column 3Connect the nearly full square

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 193One Line Puzzle level 193 opening diagram: 60 active squares, circle at row 6, column 7, diamond at row 6, column 2A turn before the final region

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 194One Line Puzzle level 194 opening diagram: 60 active squares, circle at row 6, column 5, diamond at row 7, column 3Leave space for the return

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 195One Line Puzzle level 195 opening diagram: 60 active squares, circle at row 1, column 3, diamond at row 1, column 4Bring the last regions together

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 196One Line Puzzle level 196 opening diagram: 58 active squares, circle at row 6, column 5, diamond at row 5, column 7Around a different centre

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 197One Line Puzzle level 197 opening diagram: 58 active squares, circle at row 7, column 3, diamond at row 7, column 6The open side needs a return

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 198One Line Puzzle level 198 opening diagram: 58 active squares, circle at row 4, column 6, diamond at row 5, column 8Keep the distant edge reachable

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 199One Line Puzzle level 199 opening diagram: 58 active squares, circle at row 7, column 7, diamond at row 6, column 5Across the middle connection

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 200One Line Puzzle level 200 opening diagram: 58 active squares, circle at row 8, column 5, diamond at row 3, column 1A passage for the remaining squares

58 active squares · 57 verified moves · 6 gaps inside occupied bounds

Play level →
LEVEL 201One Line Puzzle level 201 opening diagram: 56 active squares, circle at row 5, column 1, diamond at row 6, column 7Between the interrupted rows

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 202One Line Puzzle level 202 opening diagram: 56 active squares, circle at row 3, column 6, diamond at row 1, column 1The next region can wait

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 203One Line Puzzle level 203 opening diagram: 56 active squares, circle at row 1, column 6, diamond at row 3, column 1Keep a link beside the gap

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 204One Line Puzzle level 204 opening diagram: 56 active squares, circle at row 6, column 4, diamond at row 3, column 6A return through the outer region

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 205One Line Puzzle level 205 opening diagram: 56 active squares, circle at row 8, column 3, diamond at row 8, column 4Connect the two sides in order

56 active squares · 55 verified moves · 8 gaps inside occupied bounds

Play level →
LEVEL 206One Line Puzzle level 206 opening diagram: 60 active squares, circle at row 1, column 5, diamond at row 3, column 4One line around the last gaps

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 207One Line Puzzle level 207 opening diagram: 60 active squares, circle at row 4, column 1, diamond at row 3, column 7The far border comes next

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 208One Line Puzzle level 208 opening diagram: 60 active squares, circle at row 2, column 7, diamond at row 7, column 7Return through the open middle

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 209One Line Puzzle level 209 opening diagram: 60 active squares, circle at row 1, column 7, diamond at row 7, column 8The seventh round connects

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →
LEVEL 210One Line Puzzle level 210 opening diagram: 60 active squares, circle at row 7, column 3, diamond at row 4, column 7All regions on a single line

60 active squares · 59 verified moves · 4 gaps inside occupied bounds

Play level →

Questions about these puzzles

Can I undo by dragging backward?

Yes. Trace from the head to the immediately preceding square. You may repeat this to shorten the route; Undo and Backspace also work.

Does backtracking remove an earned completion?

No. Earned completion history is retained. Restart resets the current route, and each board keeps its own saved run.

Does a stuck warning reveal where I should go back?

No. The automatic nudge contains no retreat count or highlighted recovery position. It only suggests tracing back and trying another route.