Before Kingdom Hearts Birth by Sleep
The Unversed first came into being soon after Vanitas was created by Xehanort from the extracted darkness in Ventus's heart. Out of mixed feelings of self-hatred that spawned the first of them, Vanitas attempted to destroy the creatures but re-absorbed them. As a result, the negativity of the defeated Unversed worsens Vanitas's mental state as more Unversed are created in a vicious cycle that lasted until Ventus came in contact with Sora's heart. After being forced to part ways with Ventus, Vanitas is forced to fight the Unversed in another cycle of pain and suffering before finally breaking down from the strain and deciding to aid Xehanort to create χ-blade so his pain can cease to be.
Kingdom Hearts Birth by Sleep
After the Mark of Mastery exam was conducted by Eraqus, Vanitas unleashes the Unversed on the worlds as part of Xehanort's plan to get both Terra and Ventus to leave the Land of Departure. Across the worlds, the Unversed appear before and aid those with negative thoughts and emotions. Ultimately, prior to fusing back into Ventus's body as he has some of his extensions hold him at bay, Vanitas reveals the Unversed's origins and that their primary purpose was to ensure that Ventus would grow stronger with every confrontation. With Vanitas back in Ventus's body, the Unversed ceased to be.
Several varieties of Unversed appear over the course of Kingdom Hearts Birth by Sleep. Emotion was a key component in their conception and design. Thus they are seen with smiling, angry, and crying "faces", referring to the shape of their red eyes, which all Unversed share. The emblem most Unversed are christened with is also meant to represent a heart that expresses emotion.
Unversed are considered "the opposite of human life" and grow from the negative emotions produced when Vanitas was created from Ventus. By all accounts, the Unversed are extensions of Vanitas himself, allowing him to control their actions. Unlike Heartless bosses, whom are enveloped in light when defeated, the Unversed bosses are consumed in a dark flame when vanquished.
List of Unversed
Notes and references
Ads keep the KHWiki independent and free :)