- 1.5x as much experience points as a regular Pokémon, 1.7x as much if the country speaks a different language
- Masuda's Method, where Pokémon from a country that speaks a different language increases your chances of breeding a shiny Pokémon
- I've seen people trading from different countries to get PokéMiles, since you get more the farther away you are
A side effect from traded Pokémon is that if you dont have enough gym badges, they might choose to select a different move than the one you ask it to perform, "loaf around" or even take a nap in the middle of battle.
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