Vanitas

Unreleased

Vanitas (ヴァニタス) is a mysterious character introduced in Kingdom Hearts Birth by Sleep, and seems to be one of the game's antagonists.

Birth by sleep
This is a secret movie in Kingdom Hearts II Final Mix. The two are charged by Terra, and Master Xehanort responds by shifting the earth beneath them to create a rising plateau that carries Terra above the rest. Master Xehanort then lifts the ground beneath himself as well, creating a cliff much higher than the surrounding terrain. It becomes apparent that Master Xehanort and Vanitas have great power; while Vanitas strikes Terra with Thunder, and is immediately pursued by the other two knights, Terra chases after Master Xehanort, who creates a Keyblade cyclone to aid Vanitas against the two knights.

Vanitas chases and battles the two knights on the cyclone, and neither are able to overcome him. Noticing that Terra is getting closer to Master Xehanort, Vanitas directs the cyclone towards Terra, knocking him off the cliff. The two other knights watch in horror, and one of them is hit by the cyclone, crashing to the ground. The knight's helmet is gone, revealed that the knight is a blue-haired woman, confirmed by Nomura as Aqua. The third knight comes to her aid and she unleashes Reflect magic on Terra to protect him from the cyclone, which protects him from the cyclone until the cyclone pushes him up to the cliff where Master Xehanort is where it explodes, blasting the cyclone to pieces. Terra is dropped to where Xehanort is.

Terra briefly duels Master Xehanort until the old man freezes his left arm. The third knight attempts to attack Master Xehanort from behind, but Master Xehanort teleports himself behind him and grabs him by the helmet, crushing it and freezing him. Terra tries to stop him, but Vanitas reappears and hits him off the cliff with the cyclone's remains. Master Xehanort freezes the third knight's body solild and throws him off the cliff, shattering his Keyblade and helmet. Aqua catches his body and his face is revealed to have a striking resemblance to Roxas. Though frozen, he moves his eyes to indicate that he is still alive. His name is Ventus.

Master Xehanort's Keyblade reverts into a purple and blue ball of flame-like energy. Master Xehanort then raises his hand to the sky while holding the sphere, and the ball of energy promptly shoots upwards to part the gathering dark clouds, revealing what appears to be Kingdom Hearts by means not fully explained. Terra removes his helmet to look up at Kingdom Hearts as his eyes turn yellow.

Kingdom Hearts Birth by Sleep
When Master Xehanort goes missing, he takes Vanitas with him. Terra, Aqua, and Ventus are sent in search of them, as the pair's disappearance foreshadowed a great disaster.

At some point Terra meets with Master Xehanort and discusses Vanitas's fall into darkness. At another time, Master Xehanort beckoned to an unseen figure to "defeat the darkness" and "correct his mistake", while gesturing towards Vanitas.

Appearance
Vanitas wears a black and red organic-looking bodysuit and a silver helmet covered with dark glass, hiding his face from view. The appearance's suit is quite similar to Riku's Dark Mode from Kingdom Hearts and Chain of Memories. He wields a currently unnamed Keyblade that is colored in red and black, also bearing two blue eyes that were previously unique to Riku's Soul Eater and Way to the Dawn.

Abilities
Vanitas is a skilled warrior with the Keyblade and with magic. He is seen casting thunder and blizzard magic, performing complicated acrobatics, and even rides the flying Keyblades that Master Xehanort sends out.

Etymology
"Vanitas" is Latin for "vanity", "worthlessness", "nothingness", and "emptiness."

Disciple de Maître Xehanort

Trivia

 * It is shown in the TGS trailer that Vanitas has the same battle-stance as Riku, further implying a connection.