Try One Stroke Free on iPhone
Infinite puzzles. Adaptive difficulty. No forced ads.
Puzzle Mode
Solve any level — from beginner grids to complex graphs.
Puzzle Mode generates infinite puzzles that adapt to your skill level. Each puzzle presents a grid of black and white tiles. You draw a continuous one-stroke path across the grid — every tile you cross flips color (black → white, white → black). When a full row becomes one color, it clears. An outer ring around the grid adds tactical depth. There's no timer, no score pressure — just you and the puzzle. The difficulty rises or eases based on your recent performance.
Before drawing anything, look for rows that are almost entirely one color. These are your targets — plan your path to flip the remaining odd-colored tiles in those rows to trigger a clear.
Your path flips every tile it crosses. If a tile is already the right color for a row clear, don't route through it — you'd flip it to the wrong color. Sometimes the best path deliberately avoids certain tiles.
The outer border ring lets you move around the grid without flipping interior tiles. Use it to reach a different section of the grid when you need to set up clears on non-adjacent rows.
The most efficient solutions clear multiple rows with a single path. Look for paths that flip tiles in two or three rows simultaneously, creating a chain of clears.
Cleared rows shift the grid. Start by clearing bottom rows first — this can change the tile layout above, sometimes making subsequent clears easier.
Undo is unlimited and costs nothing. If a path starts flipping tiles you didn't intend, backtrack rather than restarting the entire puzzle.
Before committing to a path, mentally picture what the grid looks like after your path is drawn. Which tiles will be flipped? Will any rows be uniform? Thinking about the end state prevents wasted moves.
After solving many puzzles, you'll notice recurring tile configurations. A checkerboard row needs every other tile flipped; an almost-solid row needs just one or two flips. Learn to spot these patterns quickly.
If the game gives you an easy puzzle, it's recalibrating. Solve it quickly and move on. Harder puzzles with more complex tile layouts and larger grids will return as the adaptive system responds.
Save hints for puzzles where you've genuinely tried and stalled. Watch how the hint path uses the outer ring and which tiles it avoids — this teaches you new color-flip strategies.
One Stroke's hint system shows you one valid solution path for the current puzzle. Hints are earned through optional ad views — they're never forced on you. When you use a hint, watch the path carefully: notice how it uses the outer ring to reposition, which tiles it deliberately avoids flipping, and how it sets up row clears. Over time, studying hint solutions will improve your color-flip strategy more than just getting past a stuck puzzle.
The game tracks your recent solve rate and adjusts puzzle complexity accordingly. Solve several puzzles quickly, and you'll see larger grids, more complex tile arrangements, and layouts that require multi-step color-flip planning. Struggle with a few, and the game eases back with smaller grids and more straightforward tile patterns. This means every player naturally settles into their challenge sweet spot — you're always working at the edge of your ability without frustration.
No. Every puzzle in One Stroke is guaranteed to have at least one valid solution path that creates the necessary row clears. If you're stuck, look for rows that are closest to being one color and plan your path to complete them, or use a hint to see the solution.
Using a hint counts as completing the puzzle, but the adaptive system notes it as assisted. The difficulty won't jump as aggressively after a hinted solve compared to an unassisted one.
Infinite. Every puzzle is procedurally generated on your device with unique tile layouts — there's no level pack to exhaust. You'll never see the same puzzle twice.
Infinite puzzles. Adaptive difficulty. No forced ads.