Pokémon Brilliant Diamond and Shining Pearl for the Nintendo Switch are remakes of the original titles. This means that they have undergone some systems changes that the developers seem to feel will bring them more in line with modern titles.
One of those changes is to the XP share system, which now shares XP will all the Pokémon in a party. Previously, titles relied on XP Share items that you could give to a Pokémon to speed up their leveling without having them be active in a fight. In
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