Deduction guide · about 7 minutes
Minesweeper pattern guide
Minesweeper reasoning keeps repeating the same few shapes. Once you know the common patterns, you can read them at a glance instead of working them out every time. Understand why each pattern works before memorizing it, and you'll spot variations much more easily.
The basics behind every pattern
Every pattern below comes from two ideas: judging one number on its own, and comparing the cells two neighboring numbers share. The game's solver uses exactly these two ideas to verify every board.
① Mines left = 0, so the rest are safe
Call a number minus the confirmed mines (flags) around it the "mines left". If the mines left is 0, every closed cell around that number is safe. A plain 0 is the simplest case of this rule.
② Mines left = closed cells, so they're all mines
If a 3 has exactly three closed cells around it, all three are mines. This shows up a lot in corners and along edges, where cells have fewer neighbors.
The 1-1 pattern
Use this when two 1s sit side by side along an edge. If every closed cell the left 1 sees is also seen by the right 1, the two 1s are counting the same single mine. So the cells only the right 1 sees are safe.
The 1-2 pattern
A 1 next to a 2 points the other way. The cells the 2 shares with the 1 hold at most one mine, so the 2's other mine has to be in a cell only the 2 can see. If there's just one such cell, it's a mine — and the cell only the 1 sees is safe.
Here's the math. Call the cells above A, B, C, D from left to right. The 1 says A+B+C=1 and the 2 says B+C+D=2. Subtracting gives D−A=1, and since a cell holds either 0 or 1 mine, D must be 1 and A must be 0.
The 1-2-1 pattern
When 1, 2, 1 sit in a row along an edge, the cells above both 1s are mines, and the cell above the 2 and the outer cells are safe. It's just the 1-2 pattern applied once from each side.
The 1-2-2-1 pattern
When 1, 2, 2, 1 sit in a row, the cells above the two middle 2s are mines and the rest are safe. It's easy to mix up with 1-2-1, so think "two 2s means mines above the 2s".
Information unique to Exit Mine
Some certainties come from this game's rules and don't exist in regular minesweeper.
- The entrance's neighbors are always safe — mines are never placed next to the entrance, so its number is always 0. Your first move needs no thought.
- The exit is always safe — it never has a mine, so you can open it any time. If it shows 0, the three cells around it are all safe and the last stretch gets easy. The exit's number is a great clue for planning the end of your path.
- Diagonals aren't paths — safe cells that touch only diagonally don't connect. You need cells linked up, down, left, or right, so two mines placed diagonally act like a wall.
A checklist for when you're stuck
- Look for numbers whose flag count already equals the number. The other closed cells around them are safe.
- Look for numbers whose mines left equals their closed cells.
- Compare neighboring numbers one pair at a time. Check whether one sees a subset of the other's cells.
- If you haven't opened the exit yet, open it.
- Even a little off your path, open a cell you know is safe to get a new number.
Every board in this game is verified to be solvable to the exit with the reasoning above. If it feels like you have to guess, there's a pair of numbers you haven't compared yet.
To solve a full board step by step, see the walkthrough. For tips on lowering your record, see strategy.