How do I calculate damage for Pokémon that have Weakness or effects applied?

Follow these steps to calculate damage:

1. Start with the attack’s damage.
2. Apply any effects that affect the Attacking Pokémon.
3. Apply Weakness.
4. Apply any effects that affect the Defending Pokémon.

For example, when applying Weakness for a 50-damage attack against an opponent’s Active Pokémon that has an effect stating “This Pokémon takes –20 damage from attacks” with the Stadium card Bounded Field in play, the opponent’s Active Pokémon takes 80 damage.
50 × 2 – 20 = 80