More details have been revealed regarding the upcoming Shiny Kyogre and Shiny Groudon events for Pokémon Ultra Sun and Ultra Moon players in Japan. These Pokémon will be distributed via Serial Code in Aeon, Tsutaya, Amazon, WonderGoo, Yodobashi and other stores including Pokémon Centers from January 13 through to March 5, with the codes being redeemable until March 28. Pokémon Ultra Sun players will receive Shiny Kyogre while Pokémon Ultra Moon players will receive Shiny Groudon.
Source: Serebii
Pokémon Blog 
3 thoughts on “Shiny Groudon and Shiny Kyogre available for Pokémon Ultra Sun and Ultra Moon from January 13 in Japan”