gamesblog

Mine logic

Numbers count the mines around them. Mark every hidden square as a mine or safe — no guessing, exactly one answer. Fields grow from 5×5.

  • Logic
  • Untimed
  • 10 levels

How it plays

Some squares show a number: how many of the eight squares around it hold a mine. Numbered squares are safe. Mark every other square as a mine ✹ or safe ·.

A number that already touches its mines clears the rest of its neighbours; a number with just as many hidden neighbours as it needs makes them all mines. Comparing two neighbouring numbers settles the squares they do not share.

Levels hide more numbers, then grow the field. Every field has exactly one answer, checked by a solver — never a guess.

Keys

Space starts and skips ahead · 1–9 pick · Enter submits · Esc stops. On a phone, tap.

What it trains

This practises counting constraints and subtracting overlapping ones. It is practice at these puzzles, not a measured gain in reasoning elsewhere.

Learn

How to get better at mine logic: the method, the techniques, what each new level asks of you, and the traps the wrong answers are made of.

Your approach to each question

  1. Start with the zeros and with numbers in corners and along edges. They have the fewest neighbours — three in a corner, five on an edge — so they decide squares soonest.
  2. For each number, count its hidden neighbours, including the four diagonals, and how many of those you have already marked as mines. Compare that with the number.
  3. Mark what is forced: if the number is already met, its other hidden neighbours are safe; if its hidden neighbours are exactly as many as the mines it still needs, they are all mines.
  4. When no single number decides anything, compare two numbers that share neighbours. When the board is nearly done, count the mines left against the mine total, if it is shown.

Techniques and tricks

  • Zero clears its ring

    A 0 has no mine around it, so every hidden square touching it is safe. Mark them · at once; each one you mark makes the numbers near it easier.

  • The number is met

    When a number already touches as many marked mines as it says, every other hidden square around it is safe.

    e.g. A 2 with two ✹ beside it and three hidden squares left: all three are ·

  • Just enough room

    When a number’s hidden neighbours, plus the mines already marked, add up to exactly the number, every hidden one is a mine.

    e.g. A 3 in a corner with its three neighbours all hidden: all three are ✹

  • Subtract the overlap

    When all the hidden neighbours of one number are also neighbours of another, the difference between the two numbers is the count of mines in the squares only the second one touches.

    e.g. A 1 sees hidden squares X and Y; the 2 beside it sees X, Y and Z. X and Y hold one mine, so Z must hold the other: Z is ✹

  • Spend the mine total

    With “Tell the mine total” on, subtract the mines you have marked from the total. If what is left equals the hidden squares left, they are all mines; if it is 0, they are all safe.

    e.g. 20 mines on a 10×10, 18 marked, and the last two hidden squares no number decides: both are mines

As the levels climb

  • The ladder starts on a 5×5 with about three fifths of the safe squares showing a number, then hides as many numbers as one answer allows. With fewer numbers, more squares are decided only by comparing neighbours.
  • The field then grows: 6×6 with half the numbers shown, then the fewest; 7×7 and 8×8 the same way, starting at about 45% and 40%. On the 6×6, 7×7 and 8×8 fewest-number rungs the mines also rise slightly, from a fifth of the squares to 22%.
  • The last two rungs are 9×9 and 10×10 with the fewest numbers. There, Subtract the overlap is the main tool: when you are stuck, look for two numbers side by side whose hidden squares nearly match.
  • The clock is off unless you turn on Time pressure; then a field gets 90 seconds plus 4 seconds for every hidden square.

Traps to avoid

  • Forgetting the diagonals. A number counts all eight squares around it, not just the four that share a side.
  • Counting numbered squares as possible mines. A square that shows a number is always safe, so leave it out when you count a neighbour’s hidden squares.
  • Leaving safe squares blank. Every hidden square must be marked, and each is scored: a safe square left empty is wrong just like a missed mine.
  • Treating an edge number like a middle one. On the edge a number has five neighbours and in a corner three; a 3 in a corner fills all of them.

How to practise

  • Turn “Tell the mine total” off once the total stops being needed to finish. Without it, every square must come from the numbers.
  • Set “Largest field” to 7 while you learn to subtract overlaps, then raise it to 10.
  • Before marking, say each number’s hidden count and still-needed count — “two hidden, one needed” — to stop the diagonal miss.
  • When the working shows a first step, find that number on the field. Then check whether you used the move it names.

Levels

It is untimed unless you turn the clock on. There are 10 levels with the default settings, and the counter stops at the real top. Your level is judged on your last ten answers, every ten: 90% moves you up, below 80% moves you down, which holds most people near four in five right.

All of it is in the settings beside Start — how many answers a judgement looks at and how often it recalibrates, the thresholds, the time, which questions, how many options, and whether you see each verdict at once or review them together at the judgement. You can also jump to any level.

More logic

All games →