Barian World

The Barian World (バリアン世界 Barian Sekai), spelled Varian World in Japanese, is a dimension located in parallel world in the Yu-Gi-Oh! ZEXAL anime that is a counterpart of the Astral World. It is currently inhabited by Barian race and is now in a interdimensional war with Astral World.

Advent
The Barian World is a world made of various powerful energies resembling the Astral World, but with a darker color scheme. Unlike the Earth, it has no physical world and consists of many crystal which denizens use to make buildings and red tundra which covers most of the place.

Lake of Ill Omen
Barian World's own lake is located toward the center of the its world where Don Thousand is sealed and where Mr. Heartland ended up after falling down portal.

Residents
Barian World is mainly lead by Barian race whom they inhabit and would acquire the "Numbers" plus destroy Astral World for sake of it. It is also home to Mr. Heartland who is trapped in that world after felling through a portal and now in bug form.

Etymology
The word "Varian" could be a shortened version of "variance" which refers to a measure of how far a set of numbers is spread out.

History
Eons ago, Don Thousand face Astral himself in great battle and lost. Astral then sealed him in Lake of Ill Omen location.

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 a group of Barians 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 "Final Prophecy", 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 "Final Prophecy" 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.

When Gilag arrived on Earth, another Barian also arrived - Rei Shingetsu. A "Barian's Guardian", Rei was sent to Earth to stop the plans of the other Barians, comparing his job that of a what a police officer would perform on Earth.

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. Following Alit's ambush by Rei, Misael takes him back to the Barian World so he can recover from his wounds. After Gilag's defeat by Yuma and Rei, he is also forced to retreat to the Barian World due to his severe injuries and fading.

After Gilag and Alit are both defeated, Durbe had originally wanted to step up with Misael to defeat Yuma instead but Vector appeared before them and volunteered to go and take Yuma's "Numbers".Vector went to Earth and challenged Yuma on the intent of purposely making him win so he could bring him to "Sargasso", with Yuma thinking he had captured Rei.

Vector gave Astral "Number 66: Master Key Beetle," with the intent of allowing him to get access to the Different Dimension Airship and to the Barian World. When Yuma and the others were close enough when fighting the monsters, he warped them to "Sargasso" on different battlefields. Durbe and Misael were also waiting for them. When Yuma and his friends arrived, the Barians began their battles with Yuma, Shark and Kite, allowing their opponents to take the first turn and watched as they Xyz Summoned and took the effect damage of "Sargasso". The Barians then revealed that "Sargasso" was an active Field Spell Card that damages a player whenever they Summon an Xyz Monster

When Vector revealed his true form and angered Yuma, Vector's true plan came into motion, using "Vain - Despising Betrayal" to destroy Yuma's deck and stop "Number C39: Utopia Ray V" from attacking or activating its effect. Vector also questioned Astral's bond with Yuma, causing Astral and Yuma to form Dark ZEXAL.

He allowed Dark ZEXAL to dwindle its Life Points away until it was split apart. He then tried for a One Turn Kill but Yuma stopped it. Vector emptied Yuma's hand and set "Barian Bomb" to finish Yuma on the next turn. When Yuma drew his card and collapsed, Vector was all assured that Yuma had been defeated and he had won. Yuma and Astral reaffirmed their bond with one another and formed ZEXAL II, using its power to rewrite "Limited Barian's Force" into "Rank-Up Magic - Numeron Force" and Summoning "Number C39: Utopia Ray Victory", which was used to defeat Vector As "Sargasso" began to collapse from Vector's defeat, he told them they would not escape Sargasso. Vector, Misael and Durbe then escaped through a portal. Frustrated by his loss against Yuma, Vector dives into the center of Barian World in order to free the Barian god, Don Thousand, who grants Vector his power in exchange for locating the seven "Legendary Number" cards that sealed him away long ago. Locating some of these Numbers with assistance from Mr. Heartland, who had been transformed into a fly after falling into the Barian World, Vector uses his power to awaken Alit and Gilag.