This Ability inverts all changes to the stat stages of a Pokémon with this Ability; if an effect would lower a stat, it is increased instead, and if an effect would increase a stat, it is decreased instead. Effects that change a Pokémon's stats without affecting stat stages, such as Guts and paralysis, are not affected by Contrary.
So no, Helping Hand isn't affected by Contrary because, unlike Superpower or Sticky Web for example, it doesn't affect stat stages. So don't worry, your Azumarril's Helping Hand wouldn't cripple Malamar.
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