Trading isn't necessary in Pokémon Go but it can definitely help!Trading is a pretty important aspect of Pokémon, even being absolutely necessary to complete your Pokédex in the core games. Some Pokémon can't even be evolved without Trading. Although Trading isn't quite as crucial in Pokémon Go, it does have some pretty significant benefits. One of those benefits is Trade Evolution.
What is Trade Evolution?
In the core games, several species of Pokémon require Trading to evolve at all. You could work a Kadabra all the way to level 99, and it would still never Evolve, but the moment you Traded it, it would Evolve into an Alakazam. Pokémon Go has featured some of the species which Evolve by Trading since day one, long before Trading was even allowed in the game. These Pokémon could be Evolved in the same manner as any other Pokémon in Go: lots of Candies.
Now that Pokémon Go has introduced Trade Evolution, these Pokémon can still be evolved with Candies, but if you Trade them first, they can be evolved for free. That means a whole lot...
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Trading isn't necessary in Pokémon Go but it can definitely help!