Your party consists of up to six Pokémon (or Eggs, although your party must always contain at least one non-fainted Pokémon, unless the game is glitched) that are with you as you travel around a region. Pokémon in your party may be switched with Pokémon in the PC, and if your party is full when a new Pokémon is caught, the new Pokémon will be sent to the PC under most circumstances.
These six Pokemon are the ones you use to battle various Trainers that you encounter along your journey. The first Pokémon sent out in the battle is the one in the top-left of the screen, although if this Pokémon is fainted when the battle is started, the closest non-fainted Pokémon to the top of the screen will be sent in first.
Some abilities, when possessed by the leading member of your party, have effects on the rate of Wild Pokémon encounters.
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