The Mirage Tower was a feature that was unique to Pokémon Emerald and I thought that maybe the devs would put it in ORAS, but so far, I haven't been finding it in the remakes. I did some quick searches and they all seem to lead to the conclusion that the Mirage Tower won't be in ORAS, and one of the reasons was that there was an NPC in BW (or some other version) who mentioned that it won't reappear. Thing now is that BW's timeline is supposed to be after that of RSE, so there still might be a possibility of it being there.
Another thing that might conclude why it won't be there would be that it never was in Ruby or Sapphire in the first place, but in Emerald, so the odds of it being in ORAS again falls pretty low.
So I guess my question really is, has anyone been able to see the Mirage Tower? I personally spent 20 minutes going in and out of the desert and looking for it at its usual spot. Or maybe there is some trick (kind of like the method to unlock the Regi-Pokémon) to be able to see it first and if so, does anyone know the requirements?