When you have to summon the Pokémon instead of going to a different continent to meet them. When you want to evolve your Pokémon and evolve their skills along with it. When you find out that the Pokémon can wear jewelry and you have to evolve these equipments one by one. Everything will make you suspect that your Pokémon will one day become a ACGN game's character.
I have to admit that the graphic is good. This game has all the elements needed for a Gacha game - except that it doesn't really match up with Pokémon. If the developer is willing to concentrate on a secondary game, I think it will be more popular