>>21321613The 3rd gym had separate rooms that had certain rules/ideas for the battle. For example, one room negated OHKO moves, another had a trainer with extremely high-speed pokemon etc.
I've always liked this sort of thing, where a game changes something suddenly and you have to prepare or adapt to it.
So to me, areas where Megas appear without needing their stones seems like the next step, or at least a cool idea for one boss.
