Each of your Grass Pokémon (excluding any Shaymin) gets +40 HP. You can't use more than 1 Thankfulness Poké-Body each turn.
Choose as many Grass Energy cards from your hand as you like and attach them to your Pokémon in any way you like. If you do, this attack does 40 damage plus 20 more damage for each Grass Energy attached in this way.
Put this card onto your Active Shaymin. Shaymin LV. X can use any attack, Poké-Power, or Poké-Body from its previous Level.