Lugia, Ho-Oh, Latias and Latios are now available as Research Breakthrough encounters in Pokémon GO for the months of May and June 2019. Read on below for more details:
- Lugia, Ho-Oh, Latias, and Latios are Research Breakthrough encounters from May 1, 2019, at 1 p.m. PDT (GMT −7) through the end of June.
- Shiny Seel and Shiny Dewgong have made their Pokémon GO debuts.
- Seel or Shiny Seel is an encounter reward for the Field Research task “Catch 5 Water-type Pokémon.”
Source: Official Pokémon GO blog and @PokemonGoApp
Pokémon Blog 
2 thoughts on “Shiny Seel and Shiny Dewgong can now be found and caught in Pokémon GO for the first time”