i can not be certain that you wil get 3 lv X though...
in the other dp booster box you get at least one
but in ge there are only 4 lv X so if u got 3 in a booster box...
i dont think nintendo would put 3 lv X in a booster box
I've seen the Palkia tin and Palkia is Lv.X so.Heres what it says: You will either get Palkia, Dialga or a new legendary Pokemon! Obviously Darkrai so my guess is that since Palkia is Lv.X so will Dialga and Darkrai.