Correct a mistake without losing the puzzle

Direct conflicts explain what changed

Two cats in one row, column or region violate a quota. Two cats touching at a corner violate adjacency. GridMew highlights involved cells and names the immediate problem. Undo the latest move or remove the cat you meant to change; you do not need to restart the whole puzzle.

A placement can be wrong even when it has no immediate conflict. It might rule out every valid completion several steps later. Before building more reasoning on top of a guess, ask whether the placement was actually forced.

Recheck notes before moving cats

If a row seems to have no candidate, inspect the × notes that excluded it. A mistaken note can make a valid board look impossible. Clear or undo the unsupported note rather than forcing a cat into a ruled-out position.

Game hints use rules and placed cats. Custom solver notes become assumptions only when Treat × notes as exclusions is selected. Running the custom solver both with and without notes can help identify which kind of input caused a contradiction.

Use recovery controls deliberately

Undo reverses an ordinary board operation; Redo restores it. Restart clears the current cats and notes after confirmation, while keeping your completed record. Fixed cats remain part of the original puzzle.

Browser storage is local. Export a backup before clearing records or browser data. Import checks format and puzzle IDs before merging; an incompatible file should leave your current progress untouched. See My progress for those controls.

A real step from gm-6-0001