|Your biggest mistake was this! You should've thought twice about teaching me how to fight!|
|— Eren gains the upper hand over Reiner|
In his Titan form, Eren battles the Armored Titan while the Scout Regiment attacks the Colossal Titan. However, a whirlwind of steam coming from Bertholdt's Titan prevents them from coming close. Meanwhile, Eren is hopelessly overpowered until he recalls a special fighting technique he learned from Annie years ago. He gains the upper hand with Annie's maneuver, but a devastating interference from the Colossal Titan brings the fight to a sudden halt.
Three years ago, Reiner and Bertholdt wander through the forest outside the 104th Cadet Corps training grounds, discussing their reasons for joining the military with Eren and Armin. Reiner states his need to return to his hometown, and Bertholdt wants to join the Military Police to live safe in the interior. Eren says that he wishes to slaughter all the Titans beyond the Walls. Coming to a cliffside, the moonlight shines through the clouds, illuminating a large lake in the valley below. Reiner is surprised that Eren's will was not broken by the attack of the Titans. Reiner states his faith in Eren's ability to complete his training.
Now, at Wall Rose, Eren bitterly transforms into his Titan form, outraged at the traitors Reiner and Bertholdt have revealed themselves to be. With a powerful but ineffective punch, Eren and the Armored Titan plummet to the ground below. Hanging from the Wall, Mikasa scolds herself for being unable to decapitate Reiner and Bertholdt when she had the chance, a chance which would likely not come again. Atop the Wall, Hange orders all Scouts to jump from the Wall as the Colossal Titan swings its arm forward. Historia cries out for Ymir, still unconscious in Bertholdt's grip, and Keiji sees another Scout has been caught. The Colossal Titan opens its massive mouth, throwing Ymir and the soldier inside before snapping its jaw closed.
Section Commander Hange orders an attack on the Colossal Titan, and all Scouts spring into action. The Colossal Titan's punches are narrowly avoided by the Scouts, maneuvering behind the monster with great agility. Hange's soldiers soon acknowledge the Colossal Titan's incredibly slow movement speed, leaving it at a great disadvantage compared to their quick maneuvering. All soldiers line up for a strike at the Titan's nape, but at the last moment Bertholdt unleashes a massive continuous burst of steam and scalding-hot air, forcing the Scouts to fall back.
Hange wonders if Bertholdt is attempting to disappear as he did at Shiganshina and Trost, but Armin notices something different about his strategy in this case. Rather than vanishing instantly, the Colossal Titan is now standing in place while emitting a continuous cloud of steam, preventing any soldiers from grappling to it with omni-directional mobility gear. Hange decides that for the time being, the Scouts will wait. She orders Teams 3 and 4 led by Rashad to take position behind the Colossal Titan while Lauda's Team 2 will stand guard in front. Hange decides that once Bertholdt inevitably leaves his Titan, they must kill him without hesitation, an order which does not sit well with Armin. In the meantime, Hange leads Team 1 to the base of Wall Rose to assist in Eren's fight with the Armored Titan. Staying with Team 2, Historia and Conny carry wounded Scouts away from the combat while Nifa orders them to keep their distance. Historia is convinced that Ymir was not killed by the Colossal Titan and asks for the Scouts rescue her however they can. Conny grows worried for Reiner and Bertholdt's lack of equipment, unaware of their Titan identities and concerned for their safety.
At the base of the Wall, Reiner delivers a devastating punch to Eren's Titan, sending him falling a great distance away. Recovering from the blow, Eren's mind stews with anger towards Reiner's false attitude towards his fellow cadets years ago, and Eren regrets wishing to be as strong as him. Mikasa strikes at the Armored Titan's nape, but it leaves no damage. She recalls that in the first moments of Eren's fight, his Titan's punches were useless against Reiner as well. Unlike the Female Titan, Reiner's Titan is completely covered in impenetrable armor. Healing his wounds, Eren thinks back to the fall of Wall Maria a direct result of the unforgivable actions of Reiner and Bertholdt. As Mikasa attempts to cut through Reiner's armor to no avail, Eren's Titan rises up with disgust and fury, determined to exterminate the Armored Titan. He lands a punch aimed at Reiner's face, but the blow is soon returned in ever greater force and Eren's Titan is once again knocked back.
In a training exercise, Eren collapses on the ground from one of Annie's throws. Eren is upset with Annie's brutal force, but Annie insists that she is only returning what strength is being used against her. She suggests that Eren is supposed to be gentle with someone so delicate, but Eren says that if strength alone decided their battle he would not be the one on the ground. Annie explains that her maneuvers use the strength and size of the opponent to her advantage, skills which Eren could afford to learn. She demonstrates her throw against Eren, locking her arms under one of his own and around his head while tripping him from behind. Eren is unable to escape from her lock and yields, but Annie says that before he yields he must learn to make use of his strength and learn how to speak to girls. Eren insists that he will learn, but before their conversation can continue Reiner suddenly falls on top of Eren. Mikasa approaches the group, telling Annie to teach her the maneuver she has taught Eren. Annie says that the throw is meant for humans, though she is curious if it will work on a beast. As the two prepare to spar, the other cadets gather to watch the long-awaited brawl. Eren wonders who will emerge the victor.
Back at Wall Rose, Eren wonders why he would think back to that moment in his training at such a time. Armin calls out to Eren, saying that he will not win in any fistfight against Reiner's Titan and he should retreat to the Wall.
Eren's Titan lets out a roar, and the others worry that he has lost control. However, when the two Titans square off for a cross-counter, Eren dives beneath Reiner's arm and uses Annie's grapple against him, throwing the Armored Titan to the ground and holding it in a lock. Eren thinks to himself that the traitors' greatest flaw was teaching him how to fight, and as Reiner attempts to gain the upper hand Eren grabs his arm and locks his head between his legs, squeezing with enough force to crack Reiner's armor. He swings his legs around to lock around Reiner's arm and pin him to the ground, holding him down as he tears an arm off of the Armored Titan.
As Reiner recovers from his dismemberment, Armin suggests Eren should fall back and escape before Reiner or Bertholdt can capture him. Eren retreats to the Wall with the Scouts while Captain Hannes and the Garrison regroup with the others atop the Wall, wondering why the Colossal Titan has appeared. Asking about the situation, Historia points out Eren and the others at the base of the Wall. Hange approaches Eren's Titan, telling him to find a way to prevent Reiner from pursuing before they make their escape, suggesting he should take out Reiner's legs by some means. Eren's Titan nods in response to her orders, causing Hange to blush with awe. Armin gives Mikasa his remaining blades so she can assist in the fight.
Eren gains some hope in the situation, noting that Reiner and Bertholdt are in fact the ones who are cornered. Suddenly, the Armored Titan sheds the hardened skin at the back of its legs, gaining enough mobility to charge Eren head-on. Eren is knocked over and is nearly overpowered, but manages to throw Reiner aside.
The others wonder how the Armored Titan is suddenly so fast, but Hange states that armor of any kind must have exposed areas to allow for mobility. Recalling armor used in ancient wars, Hange notes the unarmored areas of the body are typically the armpit, groin and behind the knee.
Realizing he will be unable to stay on his feet when Reiner is more mobile, Eren allows himself to be charged and instead grips Reiner's head beneath his arm and locks his legs around Reiner's torso. With Eren holding Reiner in a lock, Mikasa maneuvers to their position and cuts at the flesh behind Reiner's left knee, crippling his mobility. Eren uses the advantage to squeeze Reiner's head with all his might, and the armor at his nape begins to shatter.
Using what mobility he has left, Reiner drags himself forward with Eren for a short distance. The Scouts cheer Eren on, believing Reiner's actions to be useless. However, Reiner stops moving after a moment before letting out a roar. Hange orders for the others to be on the lookout for summoned Titans, but the area appears to be completely clear. As the Armored Titan's nape plating shatters and sprays blood, Conny and the others atop the Wall notice the Colossal Titan beginning to move. Suddenly, the rib cage holding the Colossal Titan to the Wall breaks on one side, causing it to topple over right above Eren and Reiner. A Scout cries out a warning to the others below, but they are unable to react in time as the Colossal Titan plummets to the ground below.
Currently Publicly Available Information
Titan Martial Arts
Though not typically an impressive exhibition of power and size, martial arts is similarly effective for Titans as it is for humans. Grappling throws and holds used against a Titan opponent are sometimes more potent than a striking blow.