Following the most recent Pokémon GO update, Niantic has made Trainer Battles available to all players level 10 and above. These Trainers can now challenge someone nearby to a Trainer Battle by scanning their Battle Code. Trainers can send remote Trainer Battle challenges to their Ultra Friends or Best Friends. Trainers can also Trainer Battle against team leaders. Trainer Battles take place in one of three different Trainer Battle Leagues, and each requires a team of three Pokémon. Each Trainer Battle League has different Pokémon CP limits. Niantic has successfully rolled out Pokémon GO Trainer Battles to all players level 10 and up in less than two hours:
Source: @PokemonGoApp
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