Ability · Gen 6 · 1 Pokémon
Delta Stream
On switch-in, strong winds begin until this Ability is not active in battle.
On switch-in, the weather becomes Strong Winds, which removes the weaknesses of the Flying type from Flying-type Pokemon. This weather remains in effect until this Ability is no longer active for any Pokemon, or the weather is changed by the Desolate Land or Primordial Sea Abilities.
Delta Stream was introduced in Generation 6. 1 Pokémon and forms can have it.
Pokémon with Delta Stream
As a regular ability (1)
Mega RayquazaDelta Stream FAQ
What does Delta Stream do?
On switch-in, the weather becomes Strong Winds, which removes the weaknesses of the Flying type from Flying-type Pokemon. This weather remains in effect until this Ability is no longer active for any Pokemon, or the weather is changed by the Desolate Land or Primordial Sea Abilities.
Which Pokémon have Delta Stream?
1 Pokémon and forms can have Delta Stream: Mega Rayquaza.
Effect text from Pokémon Showdown (MIT); which Pokémon have it from Showdown's Pokédex, cross-checked against PokéAPI. Unofficial fan site.