Repaint a growing corner patch one color at a time until the whole grid turns a single shade.
Flood Fill Puzzle opens on a board of randomly painted squares in six colors. Your territory begins at the upper left, and each move recolors that whole territory. Any bordering squares that match the new color are absorbed, so the area spreads outward. Win by making the board one solid color within the allowed number of moves.
This is the Flood puzzle from a well-known open-source collection of small logic games.
The goal
The status bar under the board shows your moves against the limit, for example “3 / 25 moves”. A finished board inside the limit earns the word COMPLETED. Overshoot and you get FAILED, though you can still keep going.
The default board is 12x12 on Easy. Medium and Hard tighten the limit, since it is based on the solver’s own answer plus a few spare moves. On Hard you get no spare moves at all.
How a move works
Pick any square on the board. Your corner territory takes on that color. Every touching square of that color then becomes part of the patch. Squares connect only through their sides, never their corners.
Choosing the color the patch already has does nothing, and it does not count as a move.
Strategy notes
Look at the colors bordering your patch before each click. Pick whichever color would grab the biggest chunk, rather than the nearest one. Early on, push a long arm toward the bottom right corner. A deep reach opens many new borders at once, which makes later moves bigger.
Try to wipe out a color completely. If every square of one color is next to your patch, taking all of them removes it from the board for good. Keep an eye out for lonely single squares deep in the grid too. Plan a route that picks them up along the way, or one stray square may cost a whole move at the end.
Undo and redo are unlimited, so you can test two different orders and keep the better one. Hard sets the limit to exactly what the solver needed, but its answer is not always the shortest one, so you can sometimes do better.
Who it suits
This is a good pick for players who enjoy short, tidy puzzles with a clear goal. The default board is a manageable size, and the custom settings make it as easy or as tough as you like. It also plays well on almost any device, since every move is a single tap or click.
Controls
| Action | Keyboard | Mouse | Touch |
|---|---|---|---|
| Fill the corner region with a color | Arrow keys to move the cursor, then Enter | Left-click any square of that color | Tap any square of that color |
| Undo or redo a move | U / R | Undo move / Redo move buttons | Undo move / Redo move buttons |
| Start a new grid | N | New game button | New game button |
| Change size, colors or difficulty | — | Type menu | Type menu |
Flood Fill Puzzle FAQ
Can I play Flood Fill Puzzle on a phone or Chromebook?
Yes. Tap or click any square to pick its color. On a keyboard you can also move a cursor with the arrow keys and press Enter, use U and R for undo and redo, and press N for a new grid.
Is every grid winnable?
Yes. When a grid is made, the game's own solver works out a solution, and the move limit is based on it. Easy adds five spare moves to the solver's count, Medium adds two and Hard adds none.
What should I do if I am stuck or over the limit?
Use Undo to step back and try a different order, or Restart to go back to the starting grid. Going over the limit only marks the attempt FAILED, and you can keep filling. A Solve button will also finish the grid for you.
Can I change the grid size?
Yes. The Type menu offers presets, including a larger 16x16 board and versions with three or four colors. Custom lets you choose the width, height, anywhere from 3 to 10 colors and your number of spare moves.
