Some Pokémon have had their Ability access changed between or within generations. The list is as follows.
Changes to existing Abilities
The following sections show Pokémon that had an Ability changed from one generation to the next. Bolded text indicates a new Ability has been given to the Pokémon.
Within Generation V
Blue-Striped Basculin had its first-slot Ability changed in Pokémon Black and White Versions 2. (However, a Blue-Striped Basculin obtained in a trade in White has Rock Head.)
Generation V (Between Black/White and Black 2/White 2)
Abilities are not present in Pokémon Legends: Arceus, but all Pokémon and forms introduced in that game were assigned Abilities in the game data. Many of their Abilities were changed in Pokémon Scarlet and Violet, which do have Abilities.
The following sections show Pokémon that kept their prior Ability or Abilities, but also gained a new one in a new generation.
From Generation II to Generation III
As Generations I and II did not feature Abilities, all Pokémon introduced in those generations received at least one Ability when they were introduced in Generation III.
From Generation III to Generation IV
Several Pokémon from prior generations that had only one Ability received a second one in Generation IV.
Kubfu did not have a Hidden Ability until Pokémon Scarlet and Violet 1.0.0, where it received No Guard. This remained in version 1.1.0, but was removed in 1.2.0., leaving Kubfu with Inner Focus as its only ability, as it was in Pokémon Sword and Shield. Kubfu was unavailable during this time in Scarlet and Violet, and neither game had received Pokémon HOME support, making Kubfu with No Guard illegitimate.
These Pokémon did acquire a new ability, however, internally they are listed as new forms, preventing them from being swapped into them through an Ability Capsule or Ability Patch. All three of these Pokémon had these new forms introduced in Generation VII in relation to a form change or Evolution with forms.
