Plus

Increases Special Attack to 1.5× when a friendly Pokémon has Plus or Minus.

Full effect

This Pokémon has 1.5× its Special Attack if any friendly Pokémon has Plus or Minus. This bonus does not count as a stat modifier. If either ability is disabled by Gastro Acid, both lose their effect.

In game description

Boosts the Sp. Atk stat of the Pokémon if an ally with the Plus or Minus Ability is also in battle.

Pokemon with Plus

#0179

Mareep hidden #0180

Flaaffy hidden #0181

Ampharos hidden #0311

Plusle #0599

Klink #0600

Klang #0601

Klinklang #0702

Dedenne hidden #0849

Toxtricity Amped

Using Plus in Cobblemon

Abilities are passive and always active, so Plus costs you nothing to run. If it is marked hidden on a species above, expect it to be harder to obtain: servers differ in whether hidden abilities come from breeding, an Ability Patch, or events.

See the Pokedex for which abilities each species can have, and IVs, EVs and breeding for how to actually pass one down.