Why can't I move Pokémon out of Pokémon Bank and into Omega Ruby?

I had a lot of Pokémon in Moon that I put in Pokémon Bank to send to my Omega Ruby, but when I tried to send them, it would only let me take out a single Mudkip which I originally sent to Moon from OR. My bank box was filled with Pokémon both from past generations and Sun and Moon, but it wouldn’t let me send any others. I put my Moon cartridge back in and it let me remove all of them without problems. I don’t understand how to fix it

Pleaselog inorregisterto add a comment.

It is not possible because PokeBank is a one direction transfer from older generations to newer ones. X/Y/OR/AS are all Gen 6 games. Sun/Moon are Gen 7 games. You can go from 6 to 7, but not from 7 back to 6.

There are a number of reasons for this. For one, as I’m sure you have determined on your own, the new Pokemon in Gen 7 straight up do not exist in Gen 6. Additionally, as is common with any new generation, many Pokemon have their level-up movepools altered. Gyarados is a great example of this. The levels at which it learns most of it’s moves have been altered, particularly in the case of Rain Dance and Dragon Dance. It also now learns Hurricane, something it was previously unable to do. There are even a few Pokemon who’s Abilities have changed. Gengar, most notably, was nerfed by the loss of Levitate (now takes Super Effective ground attacks), being replaced by Cursed Body.