Necrozma is the token strong Legendary Pokémon of Gen VII. Like Rayquaza and Kyurem before it, Necrozma is the highest level Pokémon that can be caught in its games. It also shares a special, dominant relationship with the "box Legendaries" of the Sun & Moon series. Now, thanks to Pokémon Home, Necrozma can bring its terrifying power and deadly appetite to the Galar region of Pokémon Sword & Shield. Here's how.
Transferring From Sun & Moon
Necrozma made its debut in Pokémon Sun & Moon and became the center of attention in the story of Ultra Sun & Ultra Moon. That means it can be caught just once in each of those games. In Sun & Moon it can be found in Ten Carat Hill during the post-game. Just follow the quest of helping Looker track down Ultra Beasts and Necrozma's turn will come. Ultra Sun & Ultra Moon make it even easier. Due to its role in the story, the player will simply encounter it while climbing Mount Lanakila to get to the Elite Four.
Once the player catches Necrozma in those 3DS games, they can put it into Pokémon Bank. Pokémon Bank is a cloud storage app that lets players store Pokémon for $5 a year. But that's only the first step. Next is to download Pokémon Home for the Nintendo Switch.
Pokémon Home is a newer cloud storage app that's meant to eventually replace Pokémon Bank. It costs $16 a year, and can connect to Bank to facilitate mass migration from the 3DS games. Players will need to activate both Bank and Home to set up a one way transfer from the older app to the newer one. After entering a long code into their 3DS, they'll be able to transfer Necrozma, and any other Pokémon, into Pokémon Home. Once Necrozma is in Pokémon Home, it can be moved from the cloud into the player's Sword/Shield storage box.
Trading For Necrozma
Pokémon Home's mobile version has a function called the GTS that allows players to offer a Pokémon of their choice and ask for any Pokémon in return. This trade is done throguh the cloud, avoiding the need to deal with Pokémon Bank or the 3DS in general. Just please make sure to offer a fair trade for the Legendary Necozma. It's also possible to trade directly with a friend and skip relying on the kindness of internet strangers.
Transfer From Pokémon GO
There are eventual plans to allow transfers between Pokémon GO and Pokémon Home. However, Necrozma won't be coming to that game for a long time. Therefore, this is not a viable way to get Necrozma into Sword & Shield.
Evolutions & Alternate Forms
Necrozma doesn't evolve, nor does it have a Gigantamax form. What it does get are several alternate forms.
Necrozma is a being that feeds on light. That makes the sun and moon Legendaries, Solgaleo and Lunala, perfect prey. A trainer can use special items called the N-Solarizer and N-Lunarizer to attach Necrozma to these Legendaries, subjugating them to Necrozma's will and unlocking a terrible new power. This new power will take the form of either Dusk Mane or Dawn Wings Necrozma.
Both Dusk Mane and Dawn Wings Necrozma can exist in Pokémon Home and be transferred into Sword & Shield. Or players can transfer the separate Pokémon in and bind Necrozma to its host in Galar. The N-Solarizer and N-Lunarizer can be obtained from a merchant in Stow-on-Side, and can be used to both fuse and de-fuse Necrozma.
There is also an Ultra Necrozma born from a trainer imbuing Dusk Mane or Dawn Wings Necrozma with Z-crystal power. Unfortunately, Z-crystals don't exist in Galar. That means no Ultra Necrozma in Gen VIII.
What Necrozma Does In Battle
Necrozma is a Psychic-type with high Special Attack, making it a good damage dealer. Its unique Ability Prism Armor lowers super effective attack damage, letting it stay in the fight longer. It can also learn a surprising variety of moves, giving trainers the ability to build it around the rest of their team. But the true power of Necrozma comes from its alternate forms.
As Dawn Wings Necrozma it gets Ghost as a second type, pumping up its Special Attack Even further. Still, though, it use attack types like Fire and Grass to keep opponents guessing. As Dusk Make Necrozma it trades in its Special Attack for high physical Attack and Steel as a second type. This makes it a little tankier and able to draw out the power of its Dragon and Ground-type moves.