GridWits
Medium tier Technique 11 of 31 Used by Smart Hint

Naked Triple

Three cells in a house between them using only three candidates lock those digits away from the rest.

How it works

  1. 1Find three cells in one house whose candidates, taken together, are just three digits — say {2,5,7}.
  2. 2No cell needs all three; {2,5}, {5,7} and {2,7} works just as well.
  3. 3Those three cells use all three digits between them, so strike 2, 5 and 7 from the rest of the house.
Next in the ladder Hidden Triple →

Three digits confined to the same three cells clear those cells of everything else.