Effect
Storm Drain forces all single-target Water-type moves—used by any other Pokémon on the field—to target this Pokémon with 100% accuracy. This ability is especially useful in double and triple battles.
When hit by a Water-type move, the ability-bearer takes no damage and its Special Attack is raised by one stage (up to a maximum of +6 stages).
Storm Drain will activate for a Water-type Hidden Power but not for Water-type Judgment.
The ability is overridden if another Pokémon becomes the "center of attention" from moves like Follow Me or Rage Powder.
Changes
In Generation 4, Storm Drain did not increase Special Attack, nor did it grant immunity to Water-type attacks. It also did not activate for Hidden Power.
