From Bulbapedia, the community-driven Pokémon encyclopedia.
Once on the player
's game, Elyssa's Farfetch'd
is classed as an outsider Pokémon
An outsider Pokémon (Japanese: こうかんしたポケモン exchanged Pokémon) is a class of Pokémon in the Pokémon games that is not originally from the same save file as the player's.
A Pokémon is recognized as an outsider if its recorded data about its Original Trainer does not match that of the player for the current game. The exact properties checked vary between different parts of the game.
When used in a battle, outsider Pokémon may disobey the player if the player does not have the appropriate Gym Badges or island challenge Stamps. A disobedient Pokémon may use a different move, do nothing, hurt itself, or even take a nap (putting itself to sleep).
Outsider Pokémon also grow faster than native Pokémon. Outsider Pokémon gain 1.5 times the normal experience points for participating in battles. From Generation V onward, if the outsider Pokémon is from a game in a different language, it will gain 1.7 times the normal experience instead.
Outsider Pokémon also cannot be renamed by the Name Rater. Only a Pokémon's original Trainer is ever able to change its nickname.
From Generation III onward, outside Pokémon have their met location listed as "apparently met".
The exact properties checked to determine if a Pokémon is an outsider vary between different parts of the game.
A Pokémon is considered an outsider Pokémon for the purposes of Name Rater if any of the following properties of the Pokémon do not match the player's.
Experience and obedience
A Pokémon is considered an outsider Pokémon for the purposes of experience boosts and obedience if any of the following properties of the Pokémon do not match the player's.
Methods of obtaining outsider Pokémon
Outsider Pokémon can be obtained in a number of ways. Pokémon originally obtained in another player's save file obtained in a trade are outsider Pokémon. Additionally, in-game trade Pokémon are also treated as Outsider Pokémon.
Normally, the player treated as the Original Trainer of gift Pokémon they receive from NPCs will be outsider Pokémon; however, in some particular cases, such as Webster's Spearow in Gold, Silver, Crystal, HeartGold, and SoulSilver and N's Pokémon in Black 2 and White 2, the NPC is retained as the Pokémon's Original Trainer.
Pokémon obtained from event distributions usually predefined Original Trainers, and so are outsider Pokémon. Only on rare occasions, such as Pokémon Sun and Moon's Snorlium Z Munchlax and Egg distributions, do distributed Pokémon's Original Trainers match the player's.
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