The user takes sure aim at the target. This ensures the next attack does not miss the target.
If the user targets the same target again before the end of the next turn, the move it uses is guaranteed to hit. This move itself also ignores accuracy and evasion modifiers.
One hit KO moves are also guaranteed to hit, as long as the user is equal or higher level than the target. This effect also allows the user to hit Pokémon that are off the field due to moves such as Dig or Fly.