Agree with the posters that say the GX attack is too expensive.
[C][C] seems just about right for that. And that can be a very effective attack at that price. Let's say your opponent has a charged up M Mewtwo up top, needs only 2 prize cards to win and you have no way to put it down. You can Lysandre something else sure, but that only buys you enough time for your opponent to figure out a counter on the next turn.
You discard that M Mewtwo and all the energy attachments and that can seriously set your opponent back for enough time to counter attack and win. It is absolutely situational and for the right price, splashable.
All that said, 4 [C] is absolutely atrocious for the two attacks and 3 [C] isn't enough for "opponent can't retreat" being the effect. I get why they didn't go [C][C] with it because then this card becomes the new "insta-donk" card of choice in just about every troll deck imaginable. But without that price, the niche usefulness of this card is far too "niche" and not enough "usefulness".
I also kind of wonder if they are trying to keep the attacks similar to it's "normal" counterpart. If so, meh.