10 Postgame Challenges In Pokémon Sun And Moon
5. Get Cosmog And Cosmoem
This event depends on what version have the game you have so read this information carefully.
Pokémon Sun: Take your Solgaleo to the top of the Altar of the Sunne at night and go through the rift. you’ll find that the time has changed to daylight.
With Solgaleo still in your party, head to the Lake of the Moone and go to the very centre. A short cutscene will play and a Cosmog will appear for you to take. Cosmog evolves into Cosmoem at level 43, Cosmoem will then evolve into Solgaleo at level 53.
Pokémon Moon: Identical, except take your Lunala to the Altar of the Moone.