|The Marley government needed Subjects of Ymir to serve as vessels for the Nine Titans and become Marleyan Warrios.|
|— Grisha Jaeger states Marley's new Warrior program|
The Warriors (戦士 Senshi?) are a special unit of the Marleyan Armed Forces. Its members are the Subjects of Ymir under Marleyan control who are given the power to transform into one of the Nine Titans. Their primary objective is to seize the Founding Titan, which they call the "Coordinate," and bring it to Marley.
The Marleyan Warriors are expected to carry out the needs of their superiors without question or objection. From a young age, Eldians are raised to believe that their race is responsible for all the wrongdoings in the history of the world, given the fact that they are the only humans capable of transforming into Titans, the catalysts for millennia of death and chaos. With this stigma in mind, Eldian children are at times offered up to the Marley government to become Warriors so that the families of accepted children may be granted honorary Marleyan citizenship rather than face subjugation within isolated internment zones, such as the one in Liberio.
Warriors candidates who demonstrate the most exceptional performance on the battlefield are often said to be given the privilege of inheriting one of the seven Titans which Marley obtained during the Great Titan War. Due to the rarity of the Warriors, efforts are taken to ensure that they are not put into dangerous situations which could lead to the loss of one of Marley's Titans.
In recent years, the Marley Warriors with the power of the Titans have served as the main force of the Paradis Island Operation, a critical operation for Marley in which the Founding Titan must be taken from the royal family within the Walls. This mission began in the year 845 during the fall of Wall Maria and has been ongoing for the past nine years. However, Warrior Reiner Braun has claimed that after the discovery of Eren Jaeger's Titan power, this aspect of their mission is no longer necessary as long as Eren agrees to return with the Warriors to their "hometown". However, when the plan was deemed a failure after the battle of Shiganshina District, the remaining Warriors served instead as the primary means of land-based assault during the Marley Mid-East War.
Out of the many Warrior candidates enlisted by the Marleyan military, only six at a given time are able to inherit the power of the Titans. While these Warrior candidates are not spared from deadly situations in combat or infiltration missions, efforts are taken to ensure that these Warrior candidates are not killed in action if possible. After inheriting a Titan, the Warriors keep their Titans for a 13-year "term" before they are passed down to other candidates chosen for the inheritance. This term limit was not established by choice, but due to the "Curse of Ymir" which ensures that any Subject of Ymir who inherits the power of the Titans will die in 13 years after receiving the power.
Those who have inherited the power of the Titans are granted red Eldian armbands as opposed to the yellow bands given to Warrior candidates. Families of these Warriors also receive red bands.
Having been raised with Marleyan propaganda from a young age, the Warriors follow the orders of their superiors without question. For some, this is done out of blind faith to Marley and an honest belief in the information they have been indoctrinated with. For others, they follow their superiors knowing that disobedience would result in death or worse. Regardless of reasoning, the Warriors abide by their sense of duty to the nation of Marley under all circumstances.
It appears that when outside of Marleyan influence, the Warriors follow a system of "might-makes-right" when settling disagreements. An example of this is during the early stages of the Paradis Island Operation: after Marcel Galliard was eaten by a random Titan, Annie Leonhart voted to return back to Marley while Reiner Braun insisted they continue the mission. This led to a fight that Reiner won, having Annie and their remaining comrade Bertholdt Hoover help him continue on with the mission. Another instance of this occurring is the disagreement between Reiner Braun and Bertholdt Hoover against Zeke Jaeger over the fate of their fellow Warrior Annie Leonhart. While Reiner and Bertholdt wanted to venture back into the Walls in order to rescue Annie, Zeke prioritized obtaining the Founding Titan from Eren Jaeger, who would inevitably travel to Shiganshina District in search of the answers within their father's basement. The decision was made only after a brawl between Reiner's Armored Titan and Zeke's Beast Titan in which the latter brutally overpowered the former, receiving little to no injury in the process. With Zeke being the victor, his choice was the decided course of action.
The Warriors had been extremely secretive due to the nature of their mission. For five years, the identities of the Warriors who began the attack on humanity remained unknown until Annie Leonhart was the first to be caught. The remaining two Warriors, Reiner Braun and Bertholdt Hoover, were only discovered to be enemies of humanity after a link was discovered between them and Annie. Despite apparent friendships formed with their comrades, the Warriors continued to follow their true mission without question.