Does 20 damage plus 10 more damage for each Energy attached to all Pokémon (both yours and your opponent's).

Discard 2 Energy attached to Blastoise. Choose 2 of your opponent's Benched Pokémon. This attack does 60 damage to each of them. (Don't apply Weakness and Resistance for Benched Pokémon.) Blastoise can't use Double Launcher during your next turn.