The High Elf's Departure Part 1 (ハイエルフの旅立ち・上) is a special story included in the Sword Oratoria BD Volume 3 booklet.
In her room at the High Elf palace, Riveria complained to Aina about her life, stating that she couldn't even shout in her own room whenever she wanted to, and added that she wasn't her father's puppet. Several hours earlier, she had been summoned by her father to the throne room, reprimanding her for having interests unbefitting that of royalty, such as having an interest in the outside world, telling her that the world outside was filthy and full of uncivilized savages. What ultimately forced her over the edge was him ripping up her prized map of the world, prompting her to declare to Aina that she would leave the forest.
In a pub in the city of Karuna, at the same time Riveria resolved to leave, Loki and Finn were discussing High Elves, causing the former to declare that she wanted an Elf. She continued by expressing her desire to visit the High Elf Forest, which was somewhat nearby, though Finn was against the idea, explaining to her what High Elves were actually like instead of what they were in her fantasies. He was also apprehensive of the idea of adding an Elf to their Familia, as they would most likely make fun of Pallums, which made him think that recruiting Elves could be postponed. Nevertheless he gave in to her wish in the end, telling her that they would head to the High Elf Forest the next day, but told her to not be depressed if they didn't have any luck.
Three days later, during the night, Riveria put into motion her plan to leave, with Aina accompanying her. To avoid being found, the two stayed off the main path, nevertheless they soon realized that they'd been found out when they heard a flock of birds fly into the air a ways back.
Outside of the forest, Loki and Finn had reached one of the entrances to the forest after three days of travel, though they weren't able to go in as there were Elves patrolling. Even if they tried to enter elsewhere, Finn knew that they'd probably not be able to reach the castle. Fortunately, the guards heard the news about Riveria's escape, causing them to run into the forest to help, allowing the two to enter. The two followed the guards to find out what was happening.
Inside of the forest, the group of Elves trying to catch up to Riveria and Aina were already within viewing distance. The knight leader requested for her to return, asking her if she knew what she was doing, but when she ignored him, he reluctantly ordered his companions to use wind magic to stop the horses. In response, Riveria began using fire magic, and her Flare Burn cancelled their Gale Blast. Unfortunately, the force of the blast still hit Aina's horse, causing it to fall over and send her flying, and an arrow hit the Unicorn Riveria was on, causing it to slam her against a tree. The Elves caught up, quickly surrounding them, and one of them accused Aina of kidnapping Riveria, then hit her in the head with the end of his spear.
Holding Aina to her, Riveria demanded to know why they were attacking Aina, to which the leader stated that she was why Riveria was able to escape, adding that Aina would be taken back to be executed. Aina pleaded for Riveria to forget about her, prompting the latter to exclaim that she hated them and the village for not trying to change. However, the knight leader ignored her cries by claiming she'd become mentally deranged, ordering the others to capture them. Before they could do so, Finn arrived, knocking them away from the two Elves. Riveria was surprised to see him in the forest, asking why he was there, and he apologized for trespassing, telling them to ask Loki instead as he was busy fighting the Elven guards.
Loki easily guessed what was happening, offering to give Riveria a falna, pointing out that they'd be in trouble if she didn't join as Finn wouldn't be able to hold off all of the guards. Riveria accused her of threatening her, prompting the former to point out that she'd be able to protect Aina, and that she'd show her the outside world. In an attempt to protect her, Aina tried to take Riveria's place, nevertheless Riveria ordered her to stop, stating this was her departure, and agreed to accept Loki's falna as long as she didn't do anything to Aina.
While Loki was busy giving her a falna, Riveria watched Finn fight. Once the process finished, Riveria tried to join the battle, though Loki stopped her to tell her the chant for Wynn Fimbulvetr. Realizing that she'd received a falna, the knight leader became enraged, causing all of guards to try to get to her, nevertheless they weren't able to as they were hit head on by Wynn Fimbulvetr. With parts of their bodies frozen in place, there wasn't anything the guards could do. As silenced insued, Loki stated that Riveria had chant connect, allowing her to use nine magic, adding that she was the strong mage in the making.