An elite arm of the Marleyan military composed of Subjects of Ymir who were trained to harness the Power of the Titans in combat, the Warrior Unit was the main infiltrating force in the failed Paradis Island Operation, which set the events of Attack on Titan in motion. Despite being the main antagonists for the first part of the story, due to their role in the fall of Wall Maria, the Battle of Trost, and the destruction of Stohess during the Female Titan Arc, the Warriors are essentially the victim of their own circumstances, having been fed Marleyan propaganda from a very early age. Hence, even though they are Eldians by blood, they have been trained to despise the inhabitants of Paradis Island, viewing them as the devils whose existence endangers the safety of the entire world.
Many prominent members of the main cast such as Bertholdt Hoover, Annie Leonhart, Pieck Finger, Marcel Galliard, Zeke Yeager, and finally, Reiner — the protagonist of Attack on TItan from the Marleyan side — all attained the Power of the Titans by enlisting as Warriors. In service of the Marleyan military, their primary objective was the seizure of the Founding Titan from the residents of Paradis, which would effectively end the threat of the Rumbling. In bearing the grueling training and hardship they must face over the course of their military service, the main objective of most Warrior candidates is to be chosen to inherit one of the Titans in Marley's possession, which would grant them and their families the status of Honorary Marleyans, able to live beyond the Eldian internment zones.
What Is The Warrior Unit?
Often recruited between the ages of five and seven, Warriors are picked from pools of candidates who are all Subjects of Ymir. From an early age, all Subjects of Ymir — Warrior candidates or otherwise — are fed with Marleyan propaganda that casts the Eldians of Paradis as the scourge of all the Earth, responsible for the crimes of the Eldian Empire which extend centuries into the past. Hence, all Eldians grow up thinking that their race is responsible for all the tragedy and suffering that has occurred throughout history, by virtue of being the only known ethnic group that can transform into Titans. At the time of the main story of Attack on Titan, Eldians are persecuted and segregated from the general populace in most parts of the world, especially in Marley where they are made to reside in internment zones such as Liberio where they are routinely harassed by military and security officials and treated as second class citizens. Forced to wear yellow armbands that identify them as Eldians, and forbidden from exploring areas beyond the internment zoness, the regions they occupy are cramped, desolate, and riddled with poor infrastructure, offering an extremely low standard of living at the time. In this vein, the Warrior program represented an escape for many Eldian families who willingly offer up their children as potential candidates in the hope of securing Honorary Marleyan status.
After an intense period of training where their mental and physical limits are tested in combat situations, six of the candidates will inherit one of the Nine Titans once the previous holder's tenure is over, provided they demonstrated exceptional performance on the battlefield. While they are exposed to intense combat situations from the very outset, some degree of care is taken to ensure that they survive long enough to see out the end of their training. Some can inherit their Titans during early adolescence or as young adults, but they will be able to hold on to this post for a maximum of 13 years. This duration is only a product of the Curse of Ymir, where all Titan shifters die exactly 13 years after first gaining their powers. Warriors who are given the Power of the Titans wear red armbands identifying them as Honorary Marleyans, while their families are also afforded the same privilege.
The Cost Of Being An Honorary Marleyan
The unfortunate downside to all these advantages is the fact that becoming a Warrior means one must demonstrate unquestioning loyalty to Marleyan authorities on every level at all times. Even though some of the more senior members of the Warrior Unit such as Zeke Yeager or Reiner Braun have earned the trust of their Marleyan superiors, any failure to comply with orders will immediately be met with dire consequences, almost inevitably resulting in death. Most Warriors go about their duties either out blind faith, driven by the brainwashing they went through as children, or out of fear of the repercussions their insubordination could hold for them and their families. Hence, there has been little, if any, rebellion among the ranks of this unit, even when many of them possess the Power of the Titans.
Besides the 13-year tenure, which cuts their lifespans down considerably, Warriors are sometimes asked to undertake highly risky military endeavors, as in the case of the Paradis Island Operation to reclaim the Founding Titan from inside the Walls. Unfortunatrely for Marley, this operation was unsuccessful on every count, where they lost the Colossal and Female Titans and were utterly defeated by the Scouts of Paradis. As per the hierarchy within the most recent incarnation of this group, they are commanded by a Marleyan General Theo Magath, to whom Zeke Yeager serves as War Chief and second in command, Below him, Reiner Braun is the acting Vice-Chief, who supervises all the other Warriors and candidates below him. Outside Marleyan supervision, the group seemed to act in a fashion where strength superseded all, as seen in the situations where Reiner convinced Annie and Bertholdt to continue with the Paradis Island Operation after Marcels' death, and when Zeke forced Reiner to delay any attempt to rescue Annie until they had obtained the Founder.
For some, such as Reiner, the complex act of balancing their own objectives as Warriors and blending into the Scouts during his time of Paradis, caused a great strain on his mind, turning him into a broken shadow of himself on returning from the island. This, combined with their childhood hardships, and the turmoil they endured when attacking the innocent civilians of Paradis, took a toll on quite a few of the Warriors, illuminating how all the benefits they secured for their families still came at an immense cost, that some of them could never really reconcile.