Chaotic Darkness

The Chaotic Darkness (混沌の闇) known in Japan as the Darkness of Chaos is the Final Boss of Season One of Final Fantasy Brave Exvius. It is the cummulative evil of humanity's hearts that was slowly accumulated in the Crystals of Land of the Crystals as a result of multiple wars and conflict in the world of Lapis, which were then given form by Sol as a Vision in order to use it as his weapon to destroy all life.

Appearance
On its initial form the Chaotic Darkness resembles a massive foggy mass of darkness with a vaguely noticeable face. Upon closer inspection it looks like a giant skeletal monster consisting mostly of a large skull head and arms surrounded by blue flames.

On its second form it has mutated drastically, now having the shape of a deformed amalgamation of several monsters, including Sand Worm, Arachne, Intangir, White Dragon, Zu, Flan, Ariman, Architeuth, Mantises, while the skeletal first form is reduced to only a small portion tied to a bulbous mass of flesh.

Story
The Chaotic Darkness was born as a result of all the negative emotions of humanity accentuated through centuries of conflict. These negative feelings and memories began to accumulate on the Crystals for several years, shapeless but alive.

Land of the Crystals
The Chaotic Darkness is summoned as a Vision by Sol at the pinnacle of the Land of the Crystals, as his "proof" that humanity's hearts full of emotions driven by basic desires, are the source of all evil and ironically attempt to use it as a weapon to end all life, as he deems humanity unsightly.

Battle
The Chaotic Darkness is faced twice as a Boss at the end of Season One.

Trivia

 * The Chaotic Darkness is infamous amongst Japanese players due to its abnormal difficulty for a Storyline Boss. It was subsequently nerfed along Sol and the Behemoth K in later updates.