Necrozma does not evolve and does not have a pre-evolved form.
Necrozma is in the Undiscovered Egg Group. It takes Necrozma 1,250,000 Experience Points to reach Level 100.
Necrozma has a larger role in terms of plot in the upcoming Generation 7 release Pokémon Ultra Sun and Ultra Moon.
Necrozma is yet to appear in a spin-off game.
Trading Card Game
Necrozma is yet to appear in the Trading Card Game.
Necrozma is yet to appear in the anime.
Necrozma is yet to appear in the movies.
Necrozma is yet to appear in the manga.
Via Move Tutor
Related ThreadsExclusive Z-Moves for Necrozma, as well as an enhanced Rotom Dex - last post by @ Oct 12, 2017
Necrozma forms leaked and named! - last post by @ Sep 18, 2017
Necrozma Forms Types - last post by @ Sep 22, 2017
Solgaleo/Lunala/Necrozma Exclusive Z-Move - last post by @ Jun 30, 2017
Pokémon Ultra Sun and Moon reveals new Necrozma forms and download size - last post by @ Oct 14, 2017