Dragonite (sun and moon) with double dragon energy

[IILordAnticsII]

Now I'm fairly new to playing the card game, so this might be a stupid question. My friends and I don't play competitive, so our decks include cards from many sets. Leaving us with many questions from time to time.

On the Dragonite from Sunday and Moon base set, it's first attack is Dragon Wave for one grass and one electric. If you have a double dragon energy attached instead of basic energy, is it discarded after the attack? Even though it isn't technically a grass or electric energy?

 

[PokePop]

Yes, the DDE is discarded.
The attack does not specify Basic Energy and the Double Dragon Energy counts as ALL types ALL the time while attached to a Dragon Pokemon, so one energy from it would fill the Grass discard requirement and the other energy would fulfill the Lighting Energy discard requirement.

You may want to check out the Compendium document, available from the gray icon link at the top of this page.
It contains a lot of rulings that cover general game play such as "rainbow like" energy cards and how they work.

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