Mosaic
Neighborhood counting meets pattern deduction
Mosaic (also known as Fill-a-Pix) is a neighborhood-counting puzzle where each number tells you how many cells in its 3x3 neighborhood (the cell itself plus all 8 neighbors) should be filled black. By analyzing overlapping neighborhoods and their constraints, you determine which cells to fill and which to leave empty, gradually revealing a hidden picture. Think of it as Minesweeper meets Nonograms — you count neighbors like Minesweeper but reveal an image like Nonograms.
How to Play Mosaic
Number Clues
Each number tells you exactly how many cells in its 3x3 neighborhood (itself + up to 8 neighbors) should be filled black.
Fill or Empty
Every cell must be either filled (black) or empty (white). There's no third state.
Neighborhood Size Varies
Corner cells have 4-cell neighborhoods, edge cells have 6, and interior cells have 9. The number must match the filled count for that neighborhood.
Overlapping Clues
Multiple numbers share cells in their neighborhoods. Where neighborhoods overlap, deductions become possible.
Hidden Picture
The completed puzzle reveals a pixel-art image, giving you visual feedback on your progress.
Pure Logic
No guessing required. The combination of overlapping clue neighborhoods provides enough information for unique solutions.
Strategy & Solving Tips
Effective Mosaic solving means analyzing how overlapping neighborhoods constrain each other. These core techniques cover most deductions.
- If a clue equals its neighborhood size, fill all cells in that neighborhood (e.g., a "9" in the center means all 9 cells are black)
- If a clue is 0, all cells in its neighborhood are empty
- Compare a clue to its number of undecided cells minus the already-filled count to find forced fills or empties
- Look for clues where the remaining fills equal remaining undecided cells — all undecided cells must be filled
- Similarly, if a clue's filled count is already met, all remaining undecided cells in its neighborhood are empty
- Focus on areas where multiple clues overlap — their combined constraints often force a cell's state
Mosaic FAQ
Does the clue number count itself?
Yes. Each number counts itself as part of its neighborhood. A "1" in a corner (4-cell neighborhood) means exactly 1 cell is filled — which could be the clue cell itself or one of its 3 neighbors.
Do all cells have numbers?
No. Many cells are empty of clues. Their fill state must be deduced from surrounding numbered cells whose neighborhoods overlap with them.
Is this the same as Minesweeper?
Similar concept but different execution. In Minesweeper, numbers show adjacent mine count and you avoid mines. In Mosaic, numbers show how many cells should be filled, and you're actively filling them to create a picture.
What kind of pictures appear?
The hidden images are pixel-art style pictures that become recognizable as you fill cells. Common subjects include animals, objects, symbols, and geometric patterns.
Ready to Play Mosaic?
Uncover hidden pictures cell by cell in Mosaic — where every number clue narrows the possibilities and every filled cell brings the image to life.