In gen5 we could choose a NPC sprite as avatar in our trainer card. And in ORAS choose one too as avatar for our secret bases.

What if we could implement this in another level?

I was thinking in choosing a NPC as an costumizable archetype wich could have its own effect in battles.

>Examples:
Youngsteer/Lass give a evassiness boost to pokemon with low stats

Hex maniacs randomly can curse/grudge/disable a opponent pokemon per battle

Dragon tamers changes fairy's dragon immunity to dragon resistance

Ace trainer's pokemon receive less damage from mega-evolved pokemon

Swimmer's pokemon has 75% probability to evade being hit by ally's surf

Gambler's pokemon will recive a random stat boost if a move with 60 of accuracy or less hit the opponent pokemon

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Also choosing those archetypes will give you pieces of costumization signature of your choice, you can only use them if your from that archetype.

If you want post some effects you can think