How to determine what normal ability you'll get with Milotic?

I would like to have a Milotic with Marvel Scale but it has two normal abilities, that and Competitive. However Feebas only has one ability, Swift Swim. How do you know what ability you’ll get with Milotic?

If there is a way i’d really like to know. Im wanting one to be a good overall wall.

Pleaselog inorregisterto add a comment.

If the unevolved Pokémon has only one Ability, but its evolution may have one of two Abilities, then it has a 50% chance of acquiring either Ability (dependent on its personality value).Source

If a Pokemon like Feebas that only have one ability evolves, itspersonality valuesdetermine which ability it will have.

Since you cannot see these values, it appears as if it is random.If your Pokemon’s PVs give you Competitive, you can always gain 200 BP at the Battle Maison and buy anAbility Capsule.

SourceMore Info on Personality Values

If a Pokemon that has one ability evolves into a Pokemon with two possible abilities, the game will select which ability it will haveat random.(On their personality value, which is decided at random. Sorry, didn’t make that clear. xD)

Hope I helped. :)Source: Bulbapedia’s ‘Ability’ page (I don’t feel like linking >.<)