Akita is Kataru's younger twin sister.
The pair were very close, as they often played together in the village. Kataru was supportive of her, as he revealed that he wanted to spend time with her after they chose a form and assured her after Vex visited. When they both achieved their forms, the siblings were elated and acted on their promise to play before they decided to head home.
After Vex and the Ice Emperor attacked he defended his sister from Boreal but was warned to retreat. However, he didn't heed her warning and was captured as a prize of the attack.
It was shown in "A Fragile Hope," that he was under the impression that she was gone like his village. However, he learned from Lloyd that not only was she alive but she was unaware of his fate. Kataru was very relieved to learn of his sister's survival.
In "Awakenings," Kataru and his sister were reunited and he was happy to see her before happily hugging her. The siblings reconnected and Kataru comforted her on Lloyd leaving.
He first hears of him in "An Unlikely Ally," as Vex told him that the latter was approaching the castle.
In "A Fragile Hope," while in the dungeon, Kataru meets Lloyd formally. He offers friendship while they are detained, as Lloyd realizes he’s Akita's brother whom she thought was dead and vice versa, in the Ice Emperor's dungeon. Lloyd reassured him that his sister is still alive, to the his relief. Very soon, the pair are liberated by Grimfax and allied to overthrow Vex and his master.
During "Once and for All," Kataru and Grimfax then create a diversion for Lloyd to reach Zane, showing his faith in Lloyd.
In "Awakenings," because of their efforts, recovered his memories and destroyed his scepter. In the process, Kataru was reunited with his sister because of Lloyd. He was present at the ninja’s departure and bus on good terms with Lloyd.
Shortly after the Ninja left, Kataru believes he wouldn't see him again, and tries to cheer his sister up.
Zane was Kataru's captor while the former was the Ice Emperor.
In the flashback of "The Last of the Formlings," Kataru met Zane when he attacked the Formling Village under Vex's coaxing by using Boreal, leaving him and his sister Akita the only survivors with Kataru brought to the dungeons of the Castle of Ice where he spent decades inside.
Upon learning that he used to be good in "A Fragile Hope," Kataru sided with Lloyd to try and destroy his scepter, which succeeded with Zane recovering his memories and destroying it.
In "Awakenings," Kataru and Zane may have put their differences aside since it was Vex's fault that he froze his village.
As seen in "The Last of the Formlings",the Ice dragon was responsible for freezing his village. Kataru attacked the dragon when it moved to go at his sister. His actions caused the dragon to attack him, resulting in his capture and separation from his sister.
During "A Fragile Hope," Kataru voiced his dislike of the dragon when he brought up how it took him as a prize.
Vex is Kataru’s enemy.
It was shown in the flashback of "The Last of the Formlings," that they first met when Vex came to Kataru and Akita’s Choosing Ceremony. Kataru had heard stories of Vex being unable to achieve his form but was disgusted at him threatening the villagers. He reassured his sister that she will not end up like him and will find her form. When the village came under attack, Kataru stood against Vex and his master but was captured by their dragon.
As seen in "An Unlikely Ally" and "A Fragile Hope," Kataru was held captive by Vex and refused to join him, despite the possibility of freedom. In response, the general didn’t hesitate to mock Kataru on his situation of being imprisoned in a cell.
In "Once and for All," Vex is revealed to have told Zane the Formlings were evil war loving creatures to get him to attack.
During "Awakenings," Vex defeated Kataru and Grimfax, having the pair re-imprisoned and mocks their situation. Unfortunately, Zane regained his memories and released all those trapped in ice, including the Formlings. After his defeat, Kataru was present when Vex was banished to the outskirts of the Never-Realm.
Grimfax is one of Kataru’s new allies.
In "A Fragile Hope," while in the dungeon, Grimfax talks with Lloyd, asking if he can really get to Zane. After Lloyd confirms this, the Blizzard Warrior frees him and Kataru.
During "Once and for All," Kataru and Grimfax work together to fight off Vex and his soldiers so Lloyd can free Zane.
In "Awakenings," the two put up a valiant effort but they are to feed it placed in the dungeon. Fortunately, their efforts were just enough to get Zane to regain his memories and freed Never-Realm of its curse.
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