GridWits
Expert tier Technique 16 of 18 Used by Smart Hint

Pocket Overflow

If making a cell land would seal an empty cell in on all four sides, that trapped cell can't be a lone piece of sea with nowhere to connect — so it has to be land too. If taking both together overflows an island or joins two islands, the first cell was never land: it's sea.

How it works

  1. 1One step further than Land Squeeze: try the second cell of the top row as land and watch what it forces next.
  2. 2The corner beside it would then have land on both of its sides, and a lone sea cell there could never reach the rest of the water — so the corner has to be land too.
  3. 3The corner touches the 2, so it joins that island and drags the first cell in with it: three cells for a clue of 2.
  4. 4That overflow means the cell you started with was never land — it's sea.
2 4
  • Sea
  • Cells that establish the pattern
  • Where the conclusion lands
Next in the ladder Every Path Agrees →

List every way an island could still fill out its size — then cross off any that would break the water around it, like trapping a 2×2 pool. A cell in all the survivors is land; a cell in none of them is sea. Often the checks leave just one way, which settles the whole pocket at once.