Oh, my gosh--there's an actual background on a full art Trainer?! What is this madness? So few of them feature physical backgrounds.
As amazing as a quadruple Rainbow Energy sounds, I'm unsure how practical this is. You're only allowed one in your deck and it's gone from the game once it's discarded, you need to have 3 Stage 2's out, and off the top of my head, I don't recall anything currently being able to search your deck for a Special Energy. (I suppose there are cards like Mallow, though.) It seems like something you'd put in your deck on the off chance you draw it while meeting its conditions and it'll be incredible, rather than something you'd want to rely on for a crucial moment in a game. This could be silly in Gardevoir decks, though. Like, if you were staring down a Metagross with 3 energies on it with full HP, if you drew Super Boost Energy and also a Fairy Energy and a Choice Band (or if you already had those two on a Gardevoir), you'd go from from having no answer to this Metagross to being able to one-hit KO it. So it's neat and certainly has potential, but it seems unreliable at this time.
And Darkrai Prism Star sounds quite promising paired with Darkrai EX. That's about all I have to say on it, other than the artwork and the card itself looks great.