When it was first introduced in Generation III, along with Generation IV as well, the user of this Ability would receive a Special Attack increase by 50% when battling with a Pokémon that had the Plus Ability. This restriction was lifted as of Generation V, as the Special Attack boost now takes effect when battling alongside a Pokémon that has either Plus or Minus.
Minus doesn't have an effect in the overworld.
Pokémon With Minus
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