Once you've completed the main game and defeated the Elite Four, make sure you have your cover legendary (either Solgaleo or Lunala) in your party, then head over to the Altar of the Moone/Sunne on Poni Island.Įnter the portal to find yourself in an alternate dimension where it'll be the opposite time of day. Getting Cosmog is actually a very easy thing to do, but it may be a bit confusing at first.