Reading numbers, spotting patterns, and surviving the forced guess
Minesweeper is the deduction puzzle that shipped with Windows for decades and quietly taught a generation of office workers formal logic. A grid of covered cells hides a fixed number of mines. Your job is to reveal every safe cell without ever clicking a mine. Your only information is the numbers: each revealed number tells you exactly how many mines sit in the up-to-eight cells touching it.
Despite the reputation, good Minesweeper is not guesswork. The overwhelming majority of every board is solvable by pure logic - chains of deductions where one number proves a cell safe, revealing a new number, which proves another cell safe. Learning to read those chains fluently is the whole game.
A number is satisfied when the mines around it are fully accounted for. If a "1" already touches one flagged cell, every other covered cell around that 1 is guaranteed safe - open them all with confidence. The reverse deduction is just as powerful: if a "2" touches exactly two covered cells, both must be mines, so flag them. Nearly all Minesweeper logic is these two rules applied over and over: count the flags, count the covered cells, compare to the number.
Chording means clicking a satisfied number to reveal all of its remaining covered neighbors at once. Once you've flagged the one mine next to a "1", chord the 1 and every other neighbor pops open in a single action. It's dramatically faster than clicking cells individually, and because it only works when your flag count matches the number, it doubles as a built-in sanity check - if a chord does nothing, your flag count around that number is off.
After the opening cascade, your solved region has a border of numbers facing covered territory - the frontier. Scan along it looking for the easy deductions first: satisfied numbers to chord, and numbers whose covered neighbors exactly match their remaining count. Each deduction reshapes the frontier and often unlocks the next one, so sweep the whole border before concluding you're stuck.
When you see 1-2-1 in a straight line along a wall of covered cells, the solution is fixed: the mines sit above the two 1s, and the cell above the 2 is safe. The logic: the 2 needs two mines among three cells, but each 1 limits its side to a single mine - the only arrangement that works puts the mines on the outside. Spotting a 1-2-1 instantly gives you one guaranteed-safe cell and two guaranteed flags.
Its big sibling: 1-2-2-1 along a wall means the mines sit above the two 2s, and the cells above both 1s are safe. Both patterns also appear vertically, mirrored, and bent around corners - the digits are what matter, not the orientation. These two patterns alone resolve a huge share of "stuck" positions on any board.
Occasionally logic genuinely runs out - the classic case is a 50/50 between two cells that no number can distinguish, often in a corner at the end of the game. When it happens, guess deliberately rather than randomly: prefer guesses in areas where either outcome yields new information over isolated coin flips, prefer cells touched by lower numbers, and if the whole frontier is ambiguous, a cell far from all numbers (deep in unexplored territory) often carries a lower mine probability than a frontier cell. And take the guess early rather than last - a 50/50 costs the same whenever you take it, but resolving it sooner means you never waste minutes solving a board you were going to lose anyway.
PlayVersusAI offers the three classic difficulties. Beginner is a small grid with few mines - openings cascade widely, and most boards solve themselves; it's the right place to drill patterns. Intermediate roughly quadruples the area with a higher mine density, and 1-2-1 style reasoning becomes essential. Expert is the full-size board packed with mines: long deduction chains, tight corridors, and the occasional genuine forced guess. Your best time is tracked separately for each size, so there's always a personal record to chase.
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