Pretty much all it does it activate the secondary effects of attacks for Plasma Pokemon EX. It is needed to activate such excellent Pokemon such as Lugia EX (120 damage, two prizes if you KO thanks to ability), Articuno EX (Paralyzes for sure, making it perhaps the best card in the game), Heatran EX (80 damage plus 10 more damage for each damage counter on the Defending Pokemon), Deoxys EX (30 damage plus 30 more damage for each energy attached to the defending Pokemon), and Thundurus EX (discards an energy attached to the defending Pokemon.) Oh, and also Zapdos EX (120 damage), Moltres EX (120 damage), and Tornadus EX (60 damage plus 30 more damage for each Plasma Energy attached) but these three aren't very good.