Type: Null and its evolution Silvally are odd Pokémon, and I don’t just mean their chimera-like designs. Ever since Type: Null was first released, folks speculated that it might receive an alternate Form without its mask, but I don’t think anyone expected that it would evolve. I doubt anyone was imagining such a weird way of evolving either — most Pokémon transform into a bigger, stronger and tougher-looking version of themselves when they evolve, or they just turn into more than one of themselves (no offense to Magneton, Dugtrio or Vanilluxe). When Type: Null evolves into Silvally, its head and tail turn from gray to white and it loses the helmet, and that’s about it. But there could be a different reason why this evolution happens the way it does: character development.
Even when Type: Null was first revealed, we knew it had been created by humans, joining a short list of manmade Pokémon that includes the Porygon line, Mewtwo, Genesect and Magearna. According to the Pokémon Sun and Moon Official Website, it “was constructed to synthesize the strengths of various Pokémon, enabling it to adapt to any situation.” The website also says that Type: Null was created to be “powerful enough to rival those Pokémon often spoken of in mythology” in order “to complete a certain mission.” Since Type: Null is a Normal-type that combines aspects of multiple types in its design, and because part of its mask somewhat resembles the ring around Arceus’ middle, plenty of Pokémon fans figured that this Pokémon spoken of in mythology was Arceus.
Upon evolution, Silvally gains even more similarities to Arceus. Its RKS System ability has the same effect as Arceus’ Multitype, the Memory hold items work the same way as Arceus’ plates, and the move Multi-Attack changes type in the same way Judgement does (or Techno Blast, for that matter).
But why would someone create a miniature Arceus?
According to Silvally’s page on the Official Website, it “is said to have been created in order to oppose a threat.” What in Alola is seen as a threat to humans and Pokémon? Ultra Beasts. It’s not officially revealed who made Silvally, but my money’s on the Aether Foundation. For one thing, they seem to be the only organization in Alola with the necessary knowledge and resources to create a mini-Arceus, and for another, they’re researching the Ultra Beasts. If this really is the case, somebody in the Aether Foundation must have decided that only a Pokémon with the adaptability of Arceus could prove strong enough to defeat the Ultra Beasts, but it proved impossible to find and capture an Arceus, so they decided to make their own.
However, Silvally’s wild nature made it impossible to command, so they fitted it with a mask in order to control it, and it became Type: Null. In terms of game mechanics, I suppose this would count as a devolution, similar to how some of Slowking’s Pokédex entries say that Slowking will revert back to Slowpoke if the Shellder is removed from its head. In terms of story speculation, it seems as if the ends are being used to justify the means — the Ultra Beasts must be defeated, so controlling a Pokémon with technology and treating it as a nameless, faceless weapon to use against the Ultra Beasts seems like a viable strategy.
I imagine that Gladion probably stole his Type: Null from the Aether Foundation, and it seems likely that he himself might have defected from the Aether Foundation at that time. I expect that at some point during the story of Pokémon Sun and Moon, the player will receive his or her own Type: Null from someone at the Aether Foundation. The Official Website says that Type: Null evolves into Silvally when it “gains a partner it can trust.” I’m not sure whether that means it evolves through Happiness or through the Pokémon Refresh feature like Sylveon and Pokémon Amie, but it establishes something new within the Pokémon video games: a Pokémon with a character arc. Many Pokémon in the anime have character arcs as they learn and grow with their Trainers, but in the games, that was mainly left up to the player’s imagination.
Type: Null was created to be a weapon with one purpose: to destroy the Ultra Beasts. However, a Trainer who sees beyond that and values Type: Null for itself rather than its power will be able to earn its trust. When that happens, it will tear off its mask and regain its true strength. It’s almost as if Mewtwo in the anime evolved when he turned on Team Rocket and destroyed their base, or when he realized that the gift of life has value for natural Pokémon, cloned Pokémon and humans alike. From the look of things, Sun and Moon just might have the best-written story in the series (although in my opinion, they would have to surpass Black and White in order to accomplish that), but we won’t know for certain until next month.