Forsaken

The Forsaken (フォーセイクン, Fōseikun) are a new enemy introduced in Kingdom Hearts: The Keyblade War. Replicas of real hearts, they search aimlessly for their original beings, seeking to destroy them in order to gain full responsibility for their originals' bodies and hearts. They can feel negative emotions, feeding their aggression in battle. It is the lust, rage, and jealousy they feel that carries them to their targets. As the Forsaken do not possess any memory or source as to who their original beings were or are, they will attack anyone to achieve their goals. It is for this reason that the Keyblade wielders Shadow, Dawn, and Void must stop them as they travel the worlds. Born when Shadow was created from within Kingdom Hearts, effectively making him the ultimate Forsaken and giving him the power to control the lesser creatures, the Forsaken were ultimately destroyed when Shadow merged with Kingdom Hearts during the final battle of the Keyblade War.

Origin
All Forsaken were created as a side-effect of Shadow's birth from within the depths of Kingdom Hearts. They soon begin to spawn through other means, Shadow able to do so once he learns that he can control them over the course of his journey.

Nature
Forsaken are aware of the fact that they are merely replicas of true hearts. It is for this reason that they go on a desperate search for their original beings, having a goal of destroying them and gaining full responsibility for their original beings' bodies and hearts and finally allowing the Forsaken to be their own self. They are driven on by a great sense of jealously and anger, adding to their aggression and making them an even larger threat. They possess no memory or source as to who their original beings were or are, however, causing them to attack anyone to achieve their goals. While Shadow is technically the only true Forsaken, as he is a "replica" of the ultimate heart, Kingdom Hearts, he does not show any of the lesser creatures' mannerisms as having Kingdom Hearts as an original being grants him a true heart. The lesser Forsaken will obey his commands, but they are otherwise independent, his enemies just as much as Dawn's or Void's.

Appearance
Numerous varieties of Forsaken exist across the fragmented worlds created after the incident at the United Paradise, and their basic forms are greatly effected by the properties of the worlds they are found in. Despite this, all varieties of Forsaken share some key physical features. The first is their eyes. Appearing as distorted hearts, these heart-shaped eyes are distorted in a certain way for each variety. Another physical normality is the fact that all Forsaken bear a common emblem on some part of their body, this emblem merely four conjoined hearts, one upside-down heart with one rightside-up beneath it, this same image repeated sideways. The positioning of these hearts represents the fact that the Forsaken are merely replicas, or mirrors, of existing hearts. References to the heart may also be seen in other ways unique to one type of Forsaken. These references all show how deeply the Forsaken are connected to the heart.

Trivia

 * The Forsaken Emblem's appearance was derrived from a design seen on the Awakening Puzzle featured in Kingdom Hearts II Final Mix.
 * In early concept design, the Forsaken had an appearance very similar to the Unversed seen in Kingdom Hearts Birth by Sleep. This was changed to create more interesting and original beings.