Before Kingdom Hearts Birth by Sleep
The first Unversed are born soon after Vanitas is created by Master Xehanort. Vanitas attempts to destroy the creatures, but he merely absorbs them. Their negativity worsens his mental state, and this, in turn, spawns more Unversed. A vicious cycle begins that does not end until Ventus's damaged heart contacts Sora's new one. After this, Vanitas leaves Ventus and is forced to fight more Unversed. The pain and suffering this causes him leads him to submit to Master Xehanort and agree to help him forge the χ-blade.
Kingdom Hearts Birth by Sleep
After Master Eraqus conducts Terra and Aqua's Mark of Mastery exam, the Unversed are unleashed in accordance with Master Xehanort's ambitions. In each of the worlds they plague, the creatures are attracted to negativity. They ultimately cease to be after Ventus fuses with Vanitas, who reveals the Unversed only existed to make Ventus stronger.
Unversed come in many shapes, sizes, and colors. A key component of their design is emotion, thus their red eyes are made to resemble laughing, angry, and crying faces. The emblem that appears on the bodies of all Unversed represents a heart that expresses emotion.
Unversed are "the opposite of human life." They are the result of the negative emotions produced when Ventus and Vanitas were separated by Master Xehanort. The Unversed are extensions of Vanitas himself, thus they obey his every command.
List of Unversed
Notes and references
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