Reveal the top 5 cards of your deck. Flip a coin for each Energy card you find there. This attack does 50 damage times the number of heads. Shuffle the revealed cards back into your deck.

Octazooka40

Any time the Defending Pokemon tries to attack, your opponent flips a coin. If tails, that attack does nothing. (If the Defending Pokemon is no longer your opponent's Active Pokemon, this effect ends.)