Pokémon GO Ultra Unlock: Starmie Super Mega Raid Day will take place on Aug. 22 from 11 a.m. to 5 p.m. local time, featuring the Pokémon GO debut of Mega Starmie. Trainers will also have their first chance to encounter Shiny Mega Starmie, along with event bonuses, increased Remote Raid Pass limits, timed research and more.
Source: Official Pokémon GO blog
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