One of the strongest Pokémon in the entire series was introduced in Pokémon Ultra Sun and Ultra Moon in the form of Ultra Necrozma, the final breathtaking form that the Legendary Pokémon could take after absorbing all of the light it required.
This powerful Psychic/Dragon-type beast, complete with one of the highest base stat totals of all Pokémon, proved to be a massive challenge for players to overcome during their exploration of Ultra Space—and an even better companion once it was a part of their teams.
Yet to shackle its immense strengths, for Necrozma to be able to Ultra Burst into Ultra Necrozma, two factors had to be taken into account. First, Necrozma had to be fused with either Solgaleo or Lunala to become Dusk Mane Necrozma or Dawn Wings Necrozma, requiring the use of the N-Solarizer or N-Lunarizer. Afterwards, it needed to head into battle holding the Ultranecrozium Z and use its exclusive Z-Move “Light that Burns the Sky,” then finally Ultra Bursting into Ultra Necrozma. Therefore, this powerful form can only appear in battle.
Necrozma has returned alongside a plethora of other Legendary Pokémon in other games since its debut, even returning in The Indigo Mask DLC for Pokémon Scarlet and Violet. And while players will be able to awaken some of its power, there is a bit of strength that remains locked away.
Can you find the Ultranecrozium Z to get Ultra Necrozma in Pokémon Scarlet and Violet?
As of now, the concept of Z-Moves has been confined entirely to the Alola region, meaning that outside of Pokémon Sun, Moon, Ultra Sun, and Ultra Moon, it is impossible to find Z-Crystals and use Z-Moves. This means Ultra Necrozma is no longer an obtainable form of the Legendary Pokémon—a fact that also held true when Necrozma returned with story relevance in The Crown Tundra DLC for Pokémon Sword and Shield.
But Necrozma’s other forms—Dusk Mane and Dawn Wings—are still able to be created in Pokémon Scarlet and Violet through the use of the N-Solarizer and N-Lunarizer, respectively, which can be obtained from the Port Marinada auction once players have successfully captured Necrozma or transferred it to the Paldea region using Pokémon HOME.
Regardless of what players try to do, there is simply no way to trigger an Ultra Burst on Necrozma to once more unleash the power of Ultra Necrozma, meaning that—much like many of the other new features introduced in titles over the past decade—this form has been lost to time.