The Armored Titan is an evidently intelligent Titan and an elusive threat to the human race. It first appeared five years ago during the fall of Wall Maria.
|As you can see, the Armored Titan is one that specializes in hardening abilities. One slam from that body should be able to destroy both Walls and gates.|
|— A Marleyan analysis of Reiner's Armored Titan|
The defining feature of the Armored Titan was the all-encompassing layer of plated, armor-like segments of hardened skin protecting the Titan body. This armor was capable of shielding the Titan from significant amounts of damage, shielding direct hit from a cannon, breaking ultrahard steel blades of vertical maneuvering equipment when struck and withstanding the Colossus Titan's explosive transformation. However, the armor had some limitations and was not capable of protecting the user from high-power weaponry such as the Mid-East Allied Forces' anti-Titan artillery. The armor could be used for physical protection as well as offensively, dealing great damage upon impact on anything the Titan charges.
While certainly formidable, the primary disadvantage of the Armored Titan's skin was the decreased speed of the Titan form. Whether due to increased weight or restrained movement, the Armored Titan was only capable of maintaining moderate running speeds when completely armored. This could be alleviated if the user chose to shed segments of the armor to increase movement capability, such as the armor behind the knees, enabling the Titan to move with incredible speed.
A lesser-known disadvantage was that if the holder of the Founding Titan wished to, they were able to cause the hardened skin of the Armored Titan to crumble away to nothing; this left the Titan prone and extremely vulnerable to damage.However, this only seemed to apply to the current body created by transforming, as transforming into the Armored Titan later revealed it to be restored of its namesake armor.
Similar to the Female Titan, the Armored Titan was capable of utilizing crystal-like hardening around its body to at least some extent. The Armored Titan could also use this ability to create claws on its hands and feet which could be used to scale the Wall of Shiganshina District with ease.
The Armored Titan, like all the Nine Titans, was brought into the world after the death of Ymir Fritz. In the 1,700 years following her death, the Armored Titan was held in the possession of one or several of the warring Eldian houses subservient to the Founding Titan. After these seventeen centuries when Karl Fritz, the 145th King of the Fritz family, abandoned the conflicts of Eldia and relocated to Paradis Island, the Armored Titan was taken by the nation of Marley during the Great Titan War.
In the year 843, Reiner Braun was chosen to inherit the power of the Armored Titan. He would later make use of his Titan form in a war between Marley and an enemy nation, using his Armored Titan to take the brunt of enemy artillery fire.
After arriving on the island and venturing northwards to the Walls, Reiner entered Shiganshina District, the southernmost territory of Eldia, after Bertolt destroyed the south gate with his Colossus Titan. As panicked Eldians fled the city while Titans swarmed in, Reiner's Armored Titan advanced to the north gate and charged it, breaking through and breaching the northern part of Wall Maria. Reiner joined his fellow surviving Warriors in entering the walled territory during the chaos, and he would not use the Armored Titan again for another five years.
Five years after the fall of Wall Maria, the Warriors of Marley learn of Eren Yeager's unknowing possession of the Attack Titan. Believing that he may also be the current inheritor of the Founding Titan that they are searching for, Reiner does not use his Armored Titan to breach Wall Rose's northern gate after Bertolt Hoover breaches the southern gate of Trost District with his Colossus Titan as initially planned; instead, the Warriors turn their full attention towards Eren.
Over a month later, Reiner reaches a breaking point and chooses to reveal his nature as the Armored Titan as well as Bertolt's nature as the Colossus Titan to Eren, promising to leave the people of the Walls alone if he returns with them to their hometown. When Eren refuses and Mikasa attacks the two Warriors, Reiner transforms into the Armored Titan and grabs Eren. However, Eren in turn transforms into the Attack Titan and battles with Reiner.
Despite improvements to his control over the Attack Titan, the Armored Titan overpowers him initially until Eren makes use of a technique that was taught to him by Annie Leonhart some time ago, taking one of the Armored Titan's arms before retreating temporarily. Requiring more speed, Reiner begins shedding the armor behind his knees and continues his attack on Eren, but he is nonetheless overpowered by the Attack Titan again. With defeat imminent, Reiner calls for Bertolt's Colossus Titan, which falls on the two Titans in an explosive burst of steam. The Armored Titan is able to withstand the intense winds and bites Eren out of the Attack Titan. Once Bertolt exits his Titan with a captive Ymir, the Warriors escape to the nearby Titan Forest.
After some conversation in the forest, the Warriors start their retreat upon seeing signal flares from the Survey Corps approaching. Reiner uses his Armored Titan to carry Bertolt and their captives away, and the Survey Corps pursues them. The Armored Titan's retreat goes unhindered until Commander Erwin Smith charges the Titan head-on with a horde of Pure Titans following after him. The Armored Titan attempts to fight back against the Titans, and the Warriors lose Eren to the Survey Corps in the moment of vulnerability. Shortly afterward, Eren succeeds in temporarily using the Founding Titan, causing the Titans to swarm after the Warriors. The Armored Titan flees with Bertolt and Ymir, and they rest in the ruins of Shiganshina District.
Some time later, Reiner's Armored Titan battles Zeke Yeager's Beast Titan due to having disagreements over their next course of action. The Armored Titan is soundly defeated in the brawl, and Zeke states that they will wait in Shiganshina for the arrival of the Survey Corps rather than attempting to rescue Annie Leonhart.
Three months after the battle of Trost District, the Survey Corps arrive in Shiganshina and seal the southern breach using a new hardening ability acquired by the Attack Titan. Suspecting that the Warriors may be nearby, Armin Arlert proposes a search of the Wall and Reiner is found hiding within. As he is attacked by Captain Levi, Reiner uses one of his last-resort Titan powers to transfer his brain functions to the entirety of his body long enough for him to transform into the Armored Titan. As the battle of Shiganshina District begins, Reiner hardens his fingers to climb Wall Maria in order to attack the Survey Corps' horses. However, Eren's Attack Titan appears in the city and Reiner is left with a choice of attack. Reiner chooses to confront Eren, and the Attack Titan battles with the Armored Titan for a second time.
Eren's new ability to harden the Attack Titan's skin successfully deals heavy damage to the Armored Titan, but the greatest damage is dealt from the Thunder Spears, a new explosive weapon developed by the Survey Corps in recent months. The explosives tear through the armor of Reiner's nape and destroy his brain, though his consciousness transfer once again keeps him alive. The Armored Titan calls for plan B, the Colossus Titan, and shortly thereafter Bertolt arrives at Reiner's side, telling him to lie down on his back for the time being.
While Bertolt confronts the Survey Corps, Reiner follows Bertolt's advice and the Armored Titan lies down on its back, protecting Reiner from further harm and allowing for him to regenerate his body. A short while later, Reiner fully heals his brain and the Armored Titan returns to the fight, but with no memory of any events that had occurred since earlier that morning. The Survey Corps attacks Reiner with the Thunder Spears again, incapacitating it and successfully bursting Reiner from the nape of the Armored Titan. Reiner is interrogated afterward, but before he can be killed he is rescued by Zeke and Pieck's Cart Titan, who brings him atop Wall Maria. The Warriors would return to Marley afterward, abandoning Annie and Bertolt.
Four years later, Reiner is present at the battle of Fort Slava at the climax of the Marley Mid-East War, waiting on standby in an airship due to the presence of anti-Titan artillery on the ground below. Once the ground infantry succeed in destroying the armored train carrying the artillery around the fortress, Reiner eventually joins the combat as the Armored Titan after a Titan airstrike sent down with the power of Zeke's Beast Titan. Alongside Porco Galliard's Jaw Titan, the Armored Titan decimates the anti-Titan artillery set up on the walls of the fortress. When the coast is clear, Reiner's Titan signals for the Beast Titan to join the battle, where it throws spare artillery at the Mid-East Allied Forces' navy stationed in the bay nearby. However, when the ships begin to open fire on the Beast Titan, Reiner uses his Armored Titan as a shield for Zeke, receiving devastating damage in the process. Despite having lost his entire body below the head in the explosion, Reiner later recovered.
One month later during Willy Tybur's speech in Liberio, Falco Grice takes Reiner to a basement behind the stage, where he meets Eren Yeager for the first time in four years. After Eren sets aside their differences and clarifies that Reiner is not his true enemy, he takes Reiner's hand and begins to transform. In a state of panic, Reiner bites his hand to transform and protect Falco. He creates two armored hands that successfully shield the two of them from the energy blast and resulting wreckage. Reiner is unconscious following the attack and his injuries do not regenerate. Falco suspects this is due to Reiner having lost the will to live.
As the Survey Corps and Warriors battle in Liberio, Falco and Gabi Braun cry out for Reiner to save Galliard's Jaw Titan, which is about to be eaten by Eren's Attack Titan. Reiner reluctantly wakes up and transforms into an incomplete Armored Titan, which is missing much of its namesake armor. The Armored Titan manages to free the Jaw Titan, but is unable to stand again after the Attack Titan punches it across the plaza.
The Armored Titan returns to Shiganshina as part of Marley's retaliatory strike against Paradis Island. Having transformed in midair to fight Eren's Titan, the two Titans are quick to clash once again. The Armored Titan is aggressive in its attack, though is somewhat overpowered by Eren's hardened punches. Soon, the Jaw Titan comes to assist Reiner, and helped from afar by the Cart Titan's projectiles, the tide of battle is turned. The three Warriors force Eren to overexert himself by using the War Hammer Titan's construction powers to keep the Jaw and Armored Titans at bay. Eventually, the Armored Titan uses a hardened pike it had been impaled on to skewer the Attack Titan, before attempting to devour Eren. However, Reiner is stopped as Eren manages to get a hold of his Titan's head and hold him off. As the two begin a struggle, the Armored Titan is knocked off of his adversary by a projectile thrown by the Beast Titan.
The Armored Titan is caught in a daze but eventually recovers and targets the Attack Titan once more. However, it is caught in a barrage of projectiles thrown by the Beast Titan, tearing it apart. After recovering, the Armored Titan resumes fighting Eren and attempts to rouse Galliard within the mangled Jaw Titan. Soon after, Zeke lets out a scream that transforms all the affected Eldians into Pure Titans; immediately, the Armored Titan is set upon by the newly transformed Falco Grice.
Caught by surprise, the Armored Titan struggles to control both the Attack Titan and Falco. After the Beast Titan is shot by General Magath a second time, Reiner believes that Zeke is finally dead and as such, loosens the armor around the nape of the Armored Titan. However, the transformed Falco ceases in biting the nape and instead targets a nearby Galliard, who is unable to sufficiently heal his wounds. The Armored Titan soon finds itself trapped in the hardened shell of the Attack Titan; breaking free, it tries to crush Eren but its hand gets struck and blown apart by a Thunder Spear. Following the start of the Rumbling, the Armored Titan reaches Gabi and shields her from the falling debris. The Titan's armor also crumbles away however, forcing Reiner to abandon his Titan form.
After Reiner regains consciousness, he joins the combined group of the Survey Corps and Warriors who go down to the harbor to attack the Yeagerists and take the flying boat. After their initial plan fails, Reiner and Annie Leonhart transform into their Titan forms and engage the incoming enemies.
Both Titans saw initial success as they repelled the Yeagerists attacks from the Thunder Spears and gunshots from the anti-personnel vertical maneuvering equipment, however, when the Azumabito engineers enter the battlefield trying to make it to the boat, Reiner is forced to use his Titan's body to protect them leading to his nape being exposed after various Thunder Spears are fired. Later, when the Female Titan is in trouble, the Armored Titan uses his face to block them and takes the impact causing his facial armor to be destroyed followed by the rest of his face and his arms being destroyed. Just before he is finished off, Connie Springer kills the incoming Yeagerists which then allowed Pieck's Cart Titan and Falco's Jaw Titan to desmember the enemies.
After arriving to Fort Salta, Reiner jumps out of the flying boat and transforms mid-air into the Armored Titan to engage the Beast Titan that is throwing projectiles towards the flying boat. The Armored Titan successfully puts a stop to the Beast Titan and engages it through hand to hand combat.  The Titan forms of previous inheritors begin to spawn from the back of the Founder Titan and the Armored Titan eventually gets overwhelmed; Reiner notices with surprise when several Titans begin fighting the others, including both Galliard brothers and Ymir's Jaw Titans. When Jean is able to detonate the explosives located at the neck of the Founding Titan, the Armored Titan lunges towards the creature emerging from the neck and tackles it to the ground, trying to prevent it from reconnecting with the severed head.
Having withstood the Colossal Titan explosion that destroyed the remains of the Founding Titan, Reiner heads towards the the creature which also survived the blast. The anomaly then emits a gas, transforming all nearby Eldians Pure Titans. Reiner is nearly overwhelmed before the power of Titans vanishes transforming all the Eldians back into people.
- The Armored Titan ranked 2nd on the Titan Popularity Poll.
- In a blog post, Isayama revealed that Reiner's Armored Titan image was actually based on Brock Lesnar, an American professional wrestler, and former Mixed Martial Artist.