Raises the likelihood of additional effects occurring when the Pokémon uses its moves.
Serene Grace (Japanese: てんのめぐみHeavenly Blessing) is an Ability introduced in Generation III.
Effect
In battle
Serene Grace will double the chance of a move having an additional effect. For example, Psychic will have a 20% chance of lowering the target's Special Defense stat instead of its usual 10% chance, and Rock Smash will always lower an opponent's Defense by 1 level, as opposed to having a 50% chance of doing so.
Serene Grace is cumulative with the rainbow produced by using Fire Pledge and Water Pledge on the same turn (causing secondary effect probabilities to be multiplied by 4 if both modifiers are present), except that moves with a chance to flinch will only have that chance doubled once.
Although the following moves are affected by the Ability, they currently cannot be learned by any Pokémon with Serene Grace. They may, however, be called via Metronome, Mirror Move, Copycat, or Mimic, or be used by a Pokémon that gained Serene Grace by Trace or a move such as Skill Swap or Role Play.
In Pokémon HeartGold and SoulSilver only, if a Pokémon with Serene Grace breaks a rock and finds an item, the game will instead pick the item below it in the game's list, unless it was the 5% item (this effectively means it will never find the most common item).