POKÉMON TCG SM12a – Tag Team All Stars GX Booster Box (Japanese)
This set is currently not part of any English series. May be some time in 2021. Best cards to look out for from this set include: Reshiram & Charizard GX, Jirachi GX, Umbreon & Darkrai GX, Pikachu & Zekrom GX, Mewtwo & Mew GX, Greninja & Zoroark GX, and much more! For full set list click here.
1 in 250 packs = god pack = all cards GX or better!