Niantic release a new event, Water Festival from 7June to 21June, 2018 (US PDT Time).
Trainers can earn 3x stardust for catching Water-type Pokémon. And, 2 km eggs will hatch Totodile, Mudkip, and Corphish with double cCandy and stardust!
In additional, the legendary pokémon Kyogre will return to raid Battles with shiny form!!