Generation III Ability

Plus

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

Plus 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.

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

Plus Data

Introduced
Generation III
Pokémon
9
In short
Increases Special Attack to 1.5× when a friendly Pokémon has Plus or Minus.

Pokémon With Plus

9 Pokémon can have Plus.

Plus Questions & Answers

What does Plus do?
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.
How many Pokémon have Plus?
9 Pokémon can have Plus.
What Pokémon have Plus?
Mareep, Flaaffy, Ampharos, Plusle, and Klink, and 4 more Pokémon can have Plus — the full list is above.
When was Plus introduced?
Plus was introduced in Generation III.