This attack does 40 damage for each Energy attached to this Pokémon.
Look at the top 20 cards of your deck and attach any number of Energy cards you find there to your Pokémon in any way you like. Shuffle the other cards back into your deck.
I ordered 3 tins, and they made sure to send 3 different designs, thanks! Sadly 1 tin did arrive with a dent in it. It also took almost a week to be shipped.