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oh why that? Is there a reason?
"Pre-Bank" is what the cartrige people played for months and it's really fun and different and I don't understand why such a good metagame is abandoned like that :(
Thats arguable.
"True RBY" means only RBY without Moves from GSC.
So "True XY" means "Pre-Bank" because it means XY only, without moves and Pokemon from other games.