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| Bug Notification
Swarm (Japanese: むしのしらせ Bug Notification) is an Ability introduced in Generation III. Twenty-four Pokémon have this Ability, all of which are Bug-type.
When a Pokémon with Swarm uses a Bug-type move, the power will increase by 1.5× if the user has less than or equal to ⅓ of its maximum HP remaining.
Outside of battle
If the Pokémon leading the party has Swarm, the chance of encountering wild Pokémon increases. In Pokémon Emerald, this Ability also increases the rate in which the cries of wild Pokémon could be heard on the field.
Swarm will do double the damage if the Pokémon using it is below 25% of its HP.
In Pokémon Conquest, Torrent will increase user's Attack if the Pokémon using it is below ⅓ of its HP.
Pokémon with Swarm
In the anime
Swarm is yet to appear in the anime, though Ash's Sewaddle was confirmed to have this Ability in A Connoisseur's Revenge!.
In other languages