|We're not agents or anything of the sort. We were utterly powerless. Marley took our homes and conscripted us into its army. The hope that we could eventually strike back faded more every day. That is until we met... him...|
|— Yelena to Hange Zoë and Levi Ackermann |
The members of the Anti-Marleyan Volunteers seem to possess a severe grudge against Marley, in part because of the empire's aggressive policy of expansion and the take over of their native lands. Before their introduction to Zeke Jaeger, the volunteers generally had low morale due to the adversity in opposing such a powerful nation. However, after meeting Zeke the soldiers became more hopeful. The Anti-Marleyan Volunteers hold a strong devotion towards their leader, with Yelena even comparing him to a God.
The Anti-Marleyan Volunteers started off as a loose collection of rebels organized by Yelena. The members largely composed of people from different nationalities that had seen their homeland being conquered by Marley. After being forced afterwards to join the Marleyan forces and to fight for the country that oppressed them, they grouped together to try to take down Marley and secure their freedom.
As stated by Yelena, they initially had very little success and lost morale over time. After meeting Zeke Jaeger, their spirits were renewed, and the two sides joined forces. Furthermore, the volunteers originally found it difficult to mesh together with all the uncertainty amidst. However, Yelena's ruthless murders of doubtful Marleyan comrades reduced this by lowering conflict, with members seeing this as a necessary evil.
In 851, a Marleyan ship arrives at Paradis and is promptly captured and beached by Eren's Titan form. They are confronted by Hange Zoë, offering to negotiate with them. When her commanding officer refuses to listen, Yelena promptly kills him and, along with Onyankopon, accepts Hange's offer to talk.
Meeting with Hange and Levi Ackermann, Yelena and Onyankopon allow the two to inspect their weapons, explaining that Marley has not yet launched a full assault on Paradis Island due to a war they are currently caught in. Hange guesses that Yelena and her comrades are sleeper agents who have infiltrated the Marleyan army, but Yelena explains to them that they are simply conscripted soldiers who have chosen to rally around Zeke Jaeger in opposition of Marley as the Anti-Marleyan Volunteers. Forming an alliance with Paradis Island, Yelena and her comrades begin sharing their technology with the islanders, and prepare to fight back against Marley.
Yelena disguises herself as a Marleyan soldier from the Lakua military base in the west and arrives at the Warriors' seating area during Willy Tybur's production. Claiming that Magath called for them, she asks that Pieck, Galliard, and Zeke follow her. Soon after, she sends Zeke off in another direction while continuing to lead the other Warriors. They stop temporarily when Pieck suddenly hugs one of the Panzer Unit soldiers that they meet on the way. She leads them into a room, where she traps the two in a hole.
At the end of the Raid on Liberio, Yelena joins the Scouts on their airship piloted by Onyankopon. Standing in a room along with Zeke, Eren Jaeger, Armin Arlelt, Levi, and Mikasa Ackermann, she takes her fake goatee off when Levi asks her to, joking that people seemed to like it. They are soon joined by Jean Kirschtein, who brings two captives with him. Jean yells at her for not carrying out her duty of locking up the Jaw and Cart Titan, causing more soldiers than necessary to die, for which she accepts responsibility.
After returning to Paradis, Yelena and her fellow Volunteers turn over a stock of Titan serums they managed to steal from Marley to the Garrison. After receiving the serums, Dot Pyxis has his soldiers capture the Volunteers, revealing that Paradis is not willing to trust Zeke and his followers yet. Yelena is unconcerned with the betrayal, confidently declaring that the Volunteers and the Eldians will soon dine at the same table.
Dot Pyxis meets with Yelena. He brings up an event ten months ago when there was a celebration for the opening of the Trost railway. At that time, the guard watching her changed to Floch, and he escorted her to her lodgings. Now Floch has been detained for leaking information. At the same time, Eren began doing movements of his own.
After Dot Pyxis surrenders to the Jaegerists, the Volunteers are released from house arrest. They then join Yelena and Pyxis in the Shiganshina District where Yelena ostracizes the commander for provoking Zeke Jaeger.
Yelena, Onyankopon, and Greiz arrive outside the Scouts' prison cell and Yelena greets them as the heroes of Shiganshina. Conny yells at Onyankopon for siding with Yelena, but Onyankopon is unsympathetic, considering that he had been under house arrest and in about the same situation not long before.
Jean suspects that Yelena is feeling good considering that so much has gone according to Zeke's plan. They attacked Marley, they got the support of the Eldian people, and they used the wine spiked with spinal fluid to control the military. With the Founding Titan, they can destroy Marley and get revenge for their homelands. Jean calls this the real reason why they came to Paradis Island.
Onyankopon says they civilized this island, which was a century behind the rest of the world. Greiz mocks them, and Nicolo calls him a rat who sold them out. Greiz is unrepentant though, expressing his dislike for repeatedly hearing about Nicolo's affection for Sasha Braus and starts insulting her. Yelena ends Greiz's frustration by swiftly shooting him in the head. She bows as she offers an apology to the imprisoned soldiers. She has no use for anyone who would curse the Eldians as devils and clarifies that the Volunteers' goal has never been about revenge. Instead, they wish to save both Eldia and Marley from the chain of hate. Yelena then explains Zeke's euthanasia plan to them.
In the aftermath of Marley's attack on Shiganshina, Floch Forster immediately orders the arrests of all the Volunteers. Once they are gathered, Floch begins to ostracize the group by wounding one who refused to show proper respect while reminding the rest of them about the loss of their leader and the imminent destruction of their homelands. Floch then extends an offer to spare those who will lend their strength for the sake of the Eldian Empire before executing the wounded Volunteer who continued to speak out in defiance. The Volunteers can only watch their comrade's corpse with anguish as they are escorted to their cells to consider the offer.
Afterwards, Yelena is branded as a criminal for her actions along with Onyankopon who refused to continue serving the Eldian Empire. Before their execution, they are saved by the Cart Titan and brought to Magath who formed an alliance with Hange and other members of the Scout Regiment.