In His Hometown, Liberio
During Marley's President Willy's speech, Falco led Reiner to a room directly behind the stage. There, he met Eren, who had infiltrated Marley.
Reiner was shocked by Eren's appearance. He asked Eren what he was doing there, and Eren replied, "Same as you." Eren implied that he was backstage, with civilians all upstairs. He then showed Reiner the wound on his hand, suggesting that he could transform into a Titan at any time.
Eren threatened Reiner, saying, "Reiner, sit down."
Reiner, please sit down.
Reiner obediently sat down, and while listening to Willy's speech, Eren asked Reiner why they had destroyed the city walls, causing the deaths of countless innocent people.
After countless pressures, pangs of conscience, and painful struggles, Reiner finally dropped his pretense in front of Eren.
He knelt on the ground, confessing to Eren that if he hadn't insisted on continuing the mission to reclaim the Founding Titan, Eren's mother wouldn't have been eaten by a Titan. Reiner said to Eren, "Your mother being eaten by a Titan wasn't the fault of the times, it was entirely my fault. Punish me, I just want to disappear..."
Reiner confessed to Eren seemed to forgive Reiner, but ultimately decided to continue fighting. Eren helped Reiner up from his knees, then transformed, rushed out of the building, and began the battle. Reiner, however, fell unconscious while protecting Falco Grice.
Falco Grice Glaes discovered that Reiner had fallen into a coma after undergoing partial Titan transformation, concluding that it was because Reiner had lost the will to live. He decided to call for help and told the unconscious Reiner, "I, Gabi, and everyone else are your comrades."
Just as Eren was about to devour the Jaw Titan, the young warriors cried out for Reiner. Their voices finally roused the unconscious Reiner. He transformed into a Titan and snatched the Jaw Titan from Eren's grasp, but was once again knocked down by Eren. When Reiner tried to stand again, Eren judged that he still couldn't kill Reiner this time. He then left the battlefield, looking at Reiner with a sorrowful gaze, saying, "Until we meet again." Immediately afterward, Reiner's Titan collapsed from exhaustion.
Reiner and Eren's fistfight
In this chapter, Reiner's Titan form is significantly different from before; the Armored Titan that appears this time is almost a complete transformation of his original form. It is unclear whether this Titan is an evolved form of the Armored Titan or an incomplete transformation due to Reiner's exhaustion.
In chapter 104, the Armored Titan Reiner wakes up from another nightmare, drenched in cold sweat, to find himself in a hospital bed with Porco and Pieck sitting beside him. Seeing him awake, Porco hands him a bottle of alcohol, asking if he'd had another nightmare, and reassuring him that it was all just a dream. Reiner says he heard Gabi and Falco Grice's voices and asks anxiously where they are.
Magath urgently convened a meeting of the Warrior Unit to discuss countermeasures. Magath believed that the Marley army had been severely damaged and was unable to fight back independently, so they should wait six months to land on the island with the World Allied Forces for a "Scorched-Earth Operation. Reiner, on the other hand, strongly advocated launching an immediate surprise attack on Paradis Island.
Reiner strongly advocated a surprise attack on Paradis Island.
After Pieck signaled to confirm Eren's location, the Marley airship force appeared over the Shiganshina. Reiner, Magath, and Colt, along with a group of Marley soldiers, appeared among the raiding party.
Eren battles Reiner. Magath leads the Marley raiding party to Shiganshina Castle, launching an attack to seize the Founding Titan. Reiner transforms into the Armored Titan and lands, engaging Eren in their fourth duel. In hand-to-hand combat, Reiner shows no improvement over his previous attacks; his punches are sluggish and unable to Eren hits. Instead, Eren repeatedly shatters Eren's facial Armored Titan, putting him at a disadvantage. During the prolonged fight, the Jaw Titan also launches several sneak attacks on Eren, but Eren uses the War Hammer Titan's spikes to break through the combined assault of the Armored and Jaw Titans.
Marley launched a surprise attack. The Cart Titan's cannon fire pierced the Attack Titan's skull, significantly reducing its mobility. Reiner gradually gained the upper hand in the fight, gaining the opportunity to suppress the Attack Titan and preparing to devour Eren. In his inner monologue, Reiner hoped to devour the Founding Titan to end everything. Eren suddenly erupted, using his only functional right hand to lift the Armored Titan 'Armored Titan upper jaw, almost ripping its head off. At the critical moment, Zeke suddenly appeared, attacking the Armored Titan with stones and separating Reiner and Eren.
Zeke unleashed his roar, transforming a large number of Eldians had drunk wine laced with Zeke's spinal fluid into Pure Titans to fight. Among them was Falco. Falco attacked Reiner, Reiner, unable to fight two against one, had to temporarily abandon his suppression of Eren. Subsequently, the Cart Titan attacked Zeke again, defeating the Beast Titan. Reiner, believing Zeke to be dead, prepared to give up resistance and transfer the Titan's power to Falco. However, Porco Galliard, the Jaw Titan's successor and the shield of Marley, appeared. Falco's Titan devoured Porco Galliard, Reiner survived once more.
After making contact with Zeke, Eren transformed into the Founding Titan and officially activated the Rumbling. Eren's first order was to remove all Hardening artifacts, such as Annie's crystals and the walls sealing the Colossal Titan. Reiner's Armored Titan was also removed, transforming Reiner from the Armored Titan into the Rumbling Titan. Reiner then told Gabi that no one could stop Eren before falling into a coma.