When a Pokémon with Slow Start enters the battlefield its Attack and Speed stats are decreased by 50% for five turns. This does not count as a stat drop, and after the five turns the stats return to normal. The decrease is negated if the opponent uses Gastro Acid, Skill Swap or Worry Seed on the Pokémon with Slow Start.
Slow Start doesn't have an effect in the overworld.
Pokemon With This Ability
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