GridWits
Medium tier Technique 5 of 8 Used by Smart Hint

Forced Bridge

Even maxing out every other connection would leave this island short — so this connection must carry the difference.

How it works

  1. 1The 3 in the top-left corner has to spread 3 bridges across just two directions.
  2. 2If either direction carried nothing, the other would have to supply all 3 — and a connection tops out at 2, one short.
  3. 3So each direction must carry at least one bridge. The same logic applies to a 5 on an edge or a 7 anywhere.
3 3 2 2
  • Bridge to add
  • Islands that establish the pattern
Next in the ladder Saturation Seal →

Filling this connection all the way would leave both its islands full, and with them full nothing else could ever leave their group — so it would strand the highlighted islands from the rest of the board. It can't carry that many.