Vector

Vector, or Barian (バリアン Barian), is a mysterious, evil emissary from the Barian World in the Yu-Gi-Oh! ZEXAL anime. Through his manipulations and contact with Dr. Faker, he is considered the true central antagonist of the first three arcs as he was responsible for most of the events that happened, in a similar vein to Z-one in Yu-Gi-Oh! 5D's.

Appearance
Vector resembles a red version of Astral. He also has wings on his back.

Etymology
Vector introduces himself in such a way that could be mean "I am Barian" or "I am a Barian". Whether or not he used "Barian" as an alias when dealing with Faker or if the latter explanation was intended is unknown.

Abilities
In a similar manner to ZEXAL, he too can merge with another being, except that he is the only one in control.

History
Five years before the World Duel Carnival, when Dr. Faker opened the door to the Barian World, Vector appeared to him. Believing that Hart Tenjo could only be kept alive with powers from the Barian World, Faker agreed to collect the "Numbers" for Barian in order to destroy the Astral World. If Faker did not complete his task, Barian would take Hart for himself.

World Duel Carnival Finals
When Faker's plan was near completion, he Dueled Yuma Tsukumo, Reginald Kastle and Kite Tenjo. When the Duel turned towards their favor, Vector appeared and possessed Faker to continue the Duel, but eventually was defeated due to Yuma's "Number C39: Utopia Ray", "Xyz Unity" and "ZW - Ultimate Shield" combination. After the Duel, he disappeared, giving Faker control of his body back.

Yu-Gi-Oh! ZEXAL II
Alit mentioned Vector, saying he doesn't want to waste his time like Vector did when attempting to destroy the Astral World.

There was also reference to the fact that Vector is still alive somewhere.

Deck
During Dr. Faker's Duel with Yuma, Shark and Kite, Vector possesses him as he revealed everything that Barian had told him to do. He uses Dr. Faker's Deck for the duration of the Duel.