GridWits
Expert tier Technique 15 of 18 Used by Smart Hint

Land Squeeze

The mirror image of Contested Space: if making a cell land would break the board right away — overflowing the island it would join, or walling a different island off from the room it still needs — then it's sea.

How it works

  1. 1Contested Space asks what breaks if a cell becomes sea; this asks the opposite. Try the cell directly above the 4 as land.
  2. 2It touches only that island, so it would have to join it — land beside exactly one island always belongs to that island.
  3. 3The 2 in the top-right still needs one more cell, and its only two open neighbors sit right against that new land, so both would touch two islands at once and neither could ever be land.
  4. 4The 2 could then never finish, so the cell was never land: it's sea.
1 2 4
  • Sea
  • Cells that establish the pattern
  • Where the conclusion lands
Next in the ladder 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.