Barian World

The Barian World (バリアン世界 Barian Sekai) is a dimension in the Yu-Gi-Oh! ZEXAL anime that is a counterpart of the Astral World. It resembles the Astral World, but with a darker color scheme. It is not a physical world, but a world made of various powerful energies. Beings from this world cannot maintain their true forms if they go to Earth. The Astral and Barian Worlds cannot directly interact with one another as both are made of energy. According to Rei Shingetsu, Barian World is not a bad world, but its just that they have some bad/evils Barians within them.

History
When Dr. Faker entered the Barian World by sacrificing two people - Kazuma Tsukumo and Byron Arclight, he was met by Vector. Vector agreed to use the powers of his world to sustain the life of Faker's son Hart Tenjo. In exchange, Faker was to destroy the Astral World. To that end, he began gathering "Numbers" to power the Sphere Field Cannon. However, he told other people he made the pact with Vector in order to conquer the world. Faker's son, Kite, owns a robot called Orbital 7 that was fueled by Baria Crystal, an unknown fuel from the Barian World. Though Faker did not tell Kite the whole story, he was at least aware that the Barian World existed and was related to the "Numbers" in some way.

Byron Arclight (who eventually became known as Vetrix) was rescued by Durbe, Alit, Misael, and Gilag and granted the abilities of the Barian World. His saviors requested he collect the "Numbers" and destroy the Astral World as compensation for their altruism. These abilities include the power to restrain opponents with chains, and owns a Trap Card called "Angolmois", which is able to open the doorway to the Barian World. Vetrix also said that he trusts only two things - himself and the Barian World, as they are what saved him after being betrayed by Dr. Faker.

Yu-Gi-Oh! ZEXAL
Vetrix gave the Trap Card "Angolmois" to Trey which was activated during Trey's Duel against Yuma Tsukumo. It caused the gateway to the Barian World to appear, which threatened to destroy all of existence. However, Trey and Yuma worked together to close the gate.

Later in finals of WDC, Vetrix used chains that come from the Barian World on Yuma. He told Astral that his own powers would not be able to affect the material, as Astral's powers came from the Astral World.

Yu-Gi-Oh! ZEXAL II
After the conclusion of the Duel between Yuma and Kite, within this world, Durbe, Alit, Misael and Gilag, conversed about Yuma and Astral. With the defeat of both Vetrix and Faker, their agenda to manipulate humans to destroy the Astral World and gather the "Numbers" had failed. Durbe sent Gilag to Earth, who took the form of a human. There, he ended up in the middle of a gang of thieves where he held their leader, Fuma, by the neck and threw him on the ground. He then held up "Rank-Up Magic - Barian's Force" and gained control of Fuma and his gang. After that, Fuma was instructed to Duel Yuma's friends in order to lure Yuma and gather his "Numbers". Following Gilag's failed attempts to get Yuma's Numbers, back in the Barian World Durbe sent Alit to try retrieving the "Numbers" from Yuma.

After the constant failures of Gilag and Alit, Durbe decided to send Misael to Earth in order to Duel Yuma. He gave Misael three Barian's Sphere Cubes, two of which he was to give to Gilag and Alit. He then disappeared into a portal and appeared in an unknown realm and approached a giant dragon, which he sealed in a blank card.