Silvally's chimeric body is nearly identical to that of its pre-evolution; however, the fur from its head turns from gray to silver, and the membrane and spikes on its fish-like tailfin turn white. Without its control mask, its mechanical, lupine head is revealed. Its snout is metallic on its nose bridge and upper jaw, both of which lead to a triangular black nose framed by three red lines. Its upper jaw ends in a sharply pointed overbite, while its lower jaw has two visible fangs, one on each side. Its eyes have white sclerae, bright silver irises, and no pupils. These eyes are mostly surrounded by black coloration, framed along the bottom by its upper jaw. On each side of its head is a circular, metallic drive, with a white circle crossed by a metal line. The back of the crest on its head opens up, and three long spikes jut out of it. Its two ears, one on each side of its crest, are short and pointed, with black and red sections on their insides.
Once it finds a partner it trusts, Type: Null destroys its own control mask to become Silvally. It reverts to its natural, wild temperament, but it is nonetheless loyal to its Trainer, and will even risk its own life in its partner's defense. The destruction of its mask re-activates its RKS System, allowing it to change its type according to the memory attached to it; its eyes, spikes, drives, and fin membrane all change color to match its current type.
Silvally, like its pre-evolution Type: Null, seems to be based on a chimera. Parts of it also resemble a griffin. Silvally's concept also bears resemblance to Arceus. Like its pre-evolution, it also appears to be based on Frankenstein's monster due to the bolt-like objects on its face and it being created from cells of different Pokémon types.
Silvally may be a combination of silver and ally. In-universe, it was named by Gladion.