Dusk Mane Necrozma

As the storyline of Pokemon Ultra Sun progresses, Lusamine, the head of the Aether Foundation, will desire to open an Ultra Wormhole in order to stop Necrozma. After doing that exact thing with the help of Nebby, it will be up to your player to ultimately stop Necrozma once and for all. However, as you go to restore Nebby at the Altar of the Sunne, Necrozma will open an Ultra Wormhole and fuse with Nebby, thus turning into its Dusk Mane Form. It is here that you will first battle Necrozma; however, you won't be able to capture it just yet.

While in its Dusk Man Form, Necrozma will be a Psychic/Steel Type Pokemon with the ability of Prism Armor. In this given battle, it will be at Level 55 and know the moves Sunsteel Strike, Morning Sun, Psycho Cut, and Night Slash.