In Pokémon GO, Raid Battles occur when a Boss Pokémon takes over a Gym. Your goal is to defeat this powerful Pokémon. If you and your fellow Trainers are successful, you’ll be rewarded with special items and a chance at catching that Pokémon. You cannot do it alone; you’ll need help from fellow Trainers to raid the Gym (and hopefully) prevail. A list of Pokémon that appear as Raid Bosses in Pokémon GO is as follows:
Level 1
Magikarp
Bayleef
Quilava
Croconaw
Level 2
Muk
Electabuzz
Magmar
Weezing
Exeggutor
Level 3
Vaporeon
Jolteon
Flareon
Alakazam
Gengar
Arcanine
Machamp
Level 4
Venusaur
Charizard
Blastoise
Lapras
Rhydon
Tyranitar
Snorlax
Level 5 – Legendary
Lugia (July 23 – ???)
Articuno (July 23 – July 31)
Moltres (July 31 – August 7)
Zapdos (August 7 – August 14)
Source: Game Informer
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