The official Pokémon website confirmed that Legendary Pokémon are coming soon to Pokémon GO. On July 22, thousands of Trainers in Grant Park for Pokémon GO Fest and the millions of others around the world will be working together to unlock in-game bonuses for the entire Pokémon GO community. If they manage to catch enough Pokémon during the GO Fest Challenge Windows, the first Legendary Pokémon will be revealed in Grant Park. If the Trainers in Chicago succeed in defeating the Legendary Pokémon, that Pokémon will start appearing in Raid Battles around the world, after Pokémon GO Fest. After the first Legendary Pokémon will be defeated, Trainers around the World will find Legendary Eggs appearing at Gyms. If Trainers and their team are able to successfully defeat a Legendary Raid Boss, they’ll have the opportunity to catch a Legendary Pokémon. The Legendary Pokémon can be used in Gym Battles and Raid Bosses but can't be left to defend Gyms.