It should have a unique evolving animation instead of the generic animation. It needs to evoke that excitement fans have been craving...
To be able to evolve during a battle like the anime, in this case the whole exp gain has to be drastically changed, perhaps a Pokemon can be given exp after it attacks much like Fire Emblem: Awakening?
I'm not sure if GameFreak is going to give us fans the short end of the stick. As the franchise can be pushed even further but taking molasses of a time to get there.
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