Pokémon GO Battle League: Twilight Trails is now underway, introducing Mega Evolution to GO Battle League alongside a new Season of competitive formats, rewards and move updates. From Sept. 8 through Sept. 15, Trainers can compete in the Great League: Mega Edition, Ultra League: Mega Edition and Master League: Mega Edition, all of which allow Mega-Evolved Pokémon, with 4× Stardust from win rewards during this opening rotation. The new season also adds a series of limited cups and returning leagues through Dec. 1, while Mega-Evolved Pokémon will receive temporary CP reductions in the Great League: Mega Edition and Ultra League: Mega Edition when necessary to meet their respective limits. Trainers can also earn a new set of avatar rewards inspired by Ryme, the Ghost-type Gym Leader from Paldea, including her shoes at Rank 10, cap and earrings at Rank 15, outfit at Rank 20 and a Ryme-inspired pose upon reaching Legend rank. Additional rewards include encounters with Pokémon such as Toxtricity, Dondozo, Kingdra, Duraludon and Pikachu Libre, while the season brings major move changes and expanded attack availability for numerous Pokémon.
Source: Official Pokémon GO blog
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