Pattern field guide

Are there patterns in Minesweeper?

Yes. Minesweeper patterns are recurring relationships between numbered clues and their hidden neighbours. They are shortcuts for deductions you can prove, not shapes that should be applied without checking the surrounding cells.

Which Minesweeper patterns should you learn first?

PatternDirect deductionCondition to check
Saturated clueEvery remaining hidden neighbour is a mineMines still needed equals hidden neighbours
Satisfied clueEvery other hidden neighbour is safeConfirmed adjacent mines equals the clue
Subset patternSubtract the smaller constraint from the larger oneOne clue's candidate cells are contained in the other's
Wall 1-2-1Outer candidates are mines and the middle candidate is safeExact straight-wall geometry with three candidates

The pattern guide shows the geometry because the same number sequence can mean something different when extra hidden neighbours are present.

How does constraint subtraction work?

List the hidden cells controlled by two nearby clues. If one list is entirely inside the other, subtract both the cells and the mines still required. The difference tells you how many mines must occupy the extra cells. This method explains named patterns and also works on positions without a name.

How does the wall 1-2-1 pattern work?

Take a straight wall with clues 1-2-1 and exactly three hidden candidate cells beside them. Let the candidates be left, middle and right. The centre clue needs two mines, while each outer clue needs one across its two adjacent candidates. The only fitting layout places mines in the left and right candidates and leaves the middle candidate safe.

When should you use probability?

Use probability only after checking every available constraint and the remaining mine count. If a 1 touches three otherwise equivalent hidden cells and no other clue affects them, each has a one-in-three mine probability. Overlapping clues can change those odds, so the local division is not enough when other constraints apply. The solver can verify whether a position still has a forced move.

How can you practise patterns?

  1. Study one formation in the full pattern guide.
  2. State the constraint that proves each safe cell or mine.
  3. Practise on No-Guessing boards, where an accepted layout has a deduction path.
  4. Compare repeated same-mode runs in the rankings only after the deduction is reliable.

Keep the Minesweeper cheat sheet open as a quick reference, but verify the surrounding cells before applying any named pattern.