Unown [X]

Pokémon Power: [XXXXX] — Whenever 1 of your Pokémon with Unown in its name uses its Hidden Power attack, flip a coin until you get tails. That attack does 10 more damage for each heads. If you have more than 1 Unown [X] in play, use only 1 [XXXXX] each turn. | Hidden Power (10): | You may have up to 4 Basic Pokémon cards in your deck with Unown in their names.