A patchwork of colored squares, one corner to start from, and a limited number of moves. Flood Fill Puzzle unblocked hands you that setup and asks a simple question: can you turn the whole grid one color before the counter runs out?
Simon Tatham wrote it under the name Flood as part of his well-known puzzle set. Rounds are quick, but picking the right order of colors takes more thought than it first appears.
How to play Flood Fill Puzzle
The region touching the top left corner is yours. Click any square of a color and your whole region switches to that color. Every neighboring square of the same color then joins it, so the region spreads. Squares connect only through their sides.
Below the grid you see how many moves you have used out of the limit. Fill the board within the limit and the puzzle is complete. Go over and it is marked as failed, though you can still finish or undo.
The Type menu sets the grid size, number of colors and difficulty. On Hard there are no spare moves, so you must match the game's own solution.
Controls
| To… | 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 |
Tips
- Head for the middle. Pushing your region toward the center early lets it touch more colors at once later on.
- Pick the color that grabs the most. Before each move, look at which neighboring color would add the biggest chunk.
- Finish off colors that are nearly gone. If only a few squares of a color remain, clearing them removes that color from the board for good.
- Undo freely to compare. Try one color, see how much it adds, then undo and try another before you commit.
- Practice with fewer colors. Presets with three or four colors are easier and help you learn the rhythm before the full set.
Flood Fill Puzzle questions
How is the move limit set?
The game solves each grid itself and adds a few spare moves based on difficulty. Easy gives the most room, and Hard gives none.
Does choosing my own color cost a move?
No. Clicking the color your region already has does nothing at all and is not counted as a move.
Can I play with just a keyboard?
Yes. Move the cursor with the arrow keys and press Enter to fill. U and R undo and redo, and N starts a new grid.
