How to use the pattern trainer
- Read the clue row and the instruction above the mini-board.
- Select every covered cell that is forced by the visible information. A question may ask for safe cells or mines.
- Choose Check answer. The trainer compares the complete set, not merely one legal move.
- Read the proof before moving on. Use Next drill to continue; progress stays in this browser.
A pattern is a relationship between overlapping clue neighborhoods, not a picture to apply blindly. The same deduction can appear horizontally, vertically, mirrored, or against another boundary. On a full board, check every clue and covered cell touching the area before using a memorized result.
Patterns included in the drills
The 1-1 edge rule
Two adjacent 1 clues beside an edge share the same possible mine cells. When one clue has no additional covered neighbor but the second does, the extra cell touched only by the second clue is safe. The proof comes from subtracting the shared possibilities, not from assuming where the shared mine sits.
The 1-2 edge rule
The first 1 accounts for one mine in the shared covered pair. A neighboring 2 that sees the same pair plus one extra covered cell still needs a second mine, so that extra cell is forced to be a mine. Reverse or rotate the shape and the constraint remains the same.
The 1-2-1 and 1-2-2-1 formations
These longer edge patterns resolve several cells at once. In the standard 1-2-1 arrangement, the cells opposite the outside 1s are mines and the cell opposite the middle 2 is safe. The 1-2-2-1 version places mines opposite the two middle 2s while the outside cells are safe. These conclusions depend on the exact covered neighborhood: an additional hidden cell touching a clue can invalidate the shortcut.
Satisfied clues, corners and subsets
If a clue already touches the required number of flagged mines, every other covered neighbor is safe. If its remaining covered-neighbor count equals its remaining mine count, all of those neighbors are mines. Subset deductions compare two clues: when one clue's unknown set is entirely inside another's, subtract the smaller mine requirement from the larger one to learn what must happen in the extra cells.
A proof checklist for real boards
- Subtract adjacent confirmed flags from each visible clue.
- List the still-covered neighbors for each clue.
- Compare clues whose covered-neighbor sets overlap.
- Mark a cell only when every valid mine arrangement agrees.
- Inspect clues just outside the apparent pattern before acting.
If more than one arrangement remains and they disagree about the target cell, the pattern has not proved a move. Recreate the wider frontier in the Minesweeper solver instead of guessing from a cropped shape.
A practice routine that transfers to full games
First complete the six drills slowly and explain each answer in words. Next, reset progress and aim for error-free recognition rather than speed. Finally, open a No-Guessing board and pause whenever you see overlapping clues. Name the relationship before clicking. This connects the compact exercise to a board where irrelevant cells and competing clues make the same logic harder to notice.
Local progress is a convenience, not an account score. Resetting it does not affect rankings or achievements. The current trainer teaches a focused starting set; it does not cover every endgame mine-count deduction, probabilistic guess, or large constraint component.
Pattern trainer questions
Why was my answer marked wrong when one selected cell was correct?
The prompt asks for the complete forced set. Selecting one correct cell but omitting another, or adding a cell that is only possible, is incomplete proof.
Should I flag every forced mine?
Flags are useful notes, but many fast players reveal safe cells without flagging every mine. The trainer asks for mines when identifying them is the deduction being practised.
Does memorizing patterns eliminate all guesses?
No. Standard boards can contain positions with multiple valid arrangements and no forced move. Pattern knowledge reduces unnecessary guesses; No-Guessing mode filters boards through a solver so a logical route exists from the intended opening.