Flood
Why does Flood change the top-left area instead of my clicked cell?
Clicking chooses a colour; it does not choose a new starting point. The connected area containing the top-left cell changes to that colour and absorbs matching neighbours along edges.
Worked example
A matching cell touching only at a corner does not join the flooded region. Look for colours touching its boundary along an edge.
What to check on your board
Apply the rule above to your current board, then verify the remaining puzzle constraints. The example explains a local deduction; it is not a solution to every randomly generated board.
Checking your next move
Look around the edge of the current top-left region before choosing a colour. Count the connected matching areas that the change would actually absorb; a large patch elsewhere on the board does not help until it touches that boundary. Recheck the expanded boundary after each move.
Using this reference
For Flood, read the rule and the worked example together before opening the game. Separate what the rule explicitly requires from what only seems likely on the current board. A useful next move is one you can explain from the visible constraints, not merely a pattern that looks familiar.
If you get stuck, isolate a smaller part of the position and list what is still possible there. After a move, check the affected rows, regions or connections again. The reference explains the documented rules; progress, controls and save behavior belong to the linked game.
Read the developer’s manual ↗ · Open the developer’s browser version ↗
Manual inspected: · Simon Tatham & contributors · MIT