V'ni have no physical bodies, which renders them invulnerable and immortal. On the other hand, it also means they have no way to interact with the material world, and are sometimes described as "all powerless" deities for this reason. However, they are able to communicate telepathically with intelligent life. When this telepathic link is most intense, this can amount to outright possession, as the V'ni and its mortal host merge to form a single mind.
Since they cannot do anything on their own, the V'ni use mortals as tools to do their bidding. These mortals are generally organized into Granter cults, who perform the will of their patron V'ni in turn for power in the form of new spells. The main purpose of this organization is to prevent granter spells from becoming public knowledge; if a member attempts to leave the organization or leak privileged information, there are always higher-ranking members with the power to hunt them down, with the Granter's host forming the infallible highest tier of the organization.
While it is rare for Granter spells to become public knowledge, it does occasionally occur. Some scholars theorize that most of the commonly used spells and enchantments in the Locus were at one time Granter powers.
The magical knowledge of the V'ni is vast and has no known limits. For this reason, Granter cults are extremely dangerous and are best viewed with suspicion.