By using the Pradeep Sen method to see into the windows, plus creating a GUI interface using Visual Basic, and also with the use of quantum mechanics, I believe I have extrapolated the text of Lucario-GX from a larger, newly released product image of the Lucario-GX Box:
[F] Aura Strike: 30+ damage. If this Pokemon evolved from Riolu during this turn, this attack does 90 more damage.
[F][F][C] Cyclone Kick: 130 damage.
[C][C] Cantankerous Beatdown GX: 30x damage. This attack does 30 damage for each damage counter on this Pokemon. (You can’t use more than 1 GX attack in a game.)
When 1 of your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards.
Weakness: Psychic (x2)
The GX attack appears to be the same as Tauros-GX‘s.
As posted before, the Lucario-GX Box will come with a never-before-seen foil promo of Lucario-GX, a jumbo card, four booster packs, and a PTCGO code card. It was originally scheduled to release on February 23rd, but will now hit store shelves in America and Europe on March 9th.