Cosmoem

Cosmoem is a Pokémon from the series of the same name. It is a Psychic-type Pokémon introduced in the seventh generation games, Pokémon Sun and Moon. It evolves into Cosmog at level 43 before turning into Solgaleo/Lunala at 53 depending on the game

Main Games
In the introduction, Lillie escapes the Aether Foundation with Cosmog, nicknamed Nebby, in her bag. After Lusamine uses it to open holes to the Ultra Beast Dimension, Nebby evolves into Cosmoem and becomes dormant. The next part of the plot is taking Nebby to the Altar of the Sunne / Moone to save it and rescue Lusamine.