Niantic revealed today that Pokémon Go players will finally be able to capture Legendary Pokémon. They can do this by teaming up in group Raid battles where they all fight against one of the powerful creatures together. If they win, they get the Pokémon.

This is a feature that Niantic has been teasing since before Pokémon Go’s release. The addition could help bring players back to the game (and encourage them to spend more money) while keeping its current fanbase engaged. The first Legendary Raid will happen in Grant Park in Chicago during Niantic’s Pokémon Go Fest. If trainers there win, the Raid will become available around the world.

Pokémon Go has been a monumental hit on mobile since launching last year. It became a craze last summer, with parks around the country filling up with users hunting for Pokémon. While its popularity has slowed down, it still brings in plenty of money. As of June, the game passed $1.2 billion in revenue and 752 million downloads. Niantic has been busy updating the game with new Pokémon and updates to its Gym system.

Legendary Pokémon are unique in the series. They are powerful, and there’s only one of each. The promotional video above shows Pokémon’s five Legendary birds: Zapdos, Articuno, Moltres, Lugia, and Ho-Oh. The video also teases Mewtwo at the end.

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