Primal Desire: The Struggle for Trost, Part 9

Primordial Desire is the thirteenth episode of the Attack on Titan anime. It is produced by Wit Studio and Production I.G. It shows Eren finally lifting up the boulder and carrying it to the hole in the wall, with other soldiers sacrificing themselves in order to protect him and then describes the aftermath of retaking the Trost District operation.

Summary
The elite soldiers keep struggling in an attempt to defend Eren. However, Rico's squad ends up completely wiped out, leaving only her and one female soldier. As they are forced to retreat to the boulder's location, they witness the arrival of more Titans heading their way.

At this time, Jean is attempting to take a dead soldier's 3D Maneuver Gear as his own one broke, while being watched from top of the wall by Annie, Connie and now Marco as well. Having troubles to detach the gear, Jean is approached by a Titan. Thankfully, Marco manages to distract the Titan, giving Jean time necessary to take the gear and escape. Connie and Annie also rush for help and when Jean finds himself having difficulties to control the gear, Connie bumps into the Titan chasing after him in order to distract it. Jean finally manages to control the gear just to be approached by another Titan, however, he ends up being ultimately saved by Annie and all four of them successfully land on top of the wall. Suddenly, they hear loud footsteps and much to their surprise, they witness Eren in his Titan form walking towards the gate while carrying the huge boulder.

The elite team, along with Mikasa, also watching in surprise, is then approached by Armin who tells them that "Eren won" and is trying to do his job now. He notes that if he manages to reach the gate, they will win. Seeing this as their ultimate chance, Ian orders the soldiers to protect Eren even if it costs their lives. Jean, Annie, Connie and Marco also descend from top of the wall with an intention to support Eren. Afterwards, Ian tells Armin and Mikasa to go directly to Eren and then goes into action himself, but suddenly stops, surprised to see Mitabi and his squad approaching the Titans on ground. Armin claims that staying on ground is suicide, but Ian states that it's the only way they have left and heads down to successfully distract a Titan, creating a way for Eren.

As Eren keeps walking towards the hole, he notices Armin and Mikasa and gets worried that they might get eaten by Titans. The soldiers continue luring the Titans, however, some of them are caught by them, including Mitabi, who gets crushed by a Titan's hand. Eren then recalls Armin questioning his motive for going outside. He states to himself that when people are born, they are free and people who deny that, no matter how strong they are, don't matter. Believing that seeing the world outside would make one the freest person, he keeps walking forward, determined to fight no matter how cruel the world is.

Meanwhile, the soldiers keep falling into Titans' hands and Mikasa and Armin witness Ian's attempt to save a soldier just to get eaten himself. As one more Titan stands in Eren's way, Rico charges forward, cutting through its eye, with Mikasa finishing the job. Finally reaching the hole, Eren, while being encouraged by Armin, drops the boulder, successfully blocking the entrance to Trost. With tears in her eyes, a delighted Rico says that the soldiers didn't die in vain and shoots a yellow signal flare as a message that the mission has been accomplished. Seeing this, Dot Pixis immediately orders to send reinforcements and rescue the elite team.

With more Titans approaching, Rico exclaims that they have to climb the wall as soon as possible, but Mikasa rushes to Eren who is still partially attached to the Titan's body. Rico quickly decides that they have to cut him off and herself does the job. However, at that moment, two Titans reach them and as they are about to attack, they are slayed by a mysterious soldier. With Eren noticing the "wings of freedom" on the soldier's back, their savior turns out to be Levi. Standing on top of the killed Titan, Levi looks at Eren and others and questions the situation.

After that, both Stationary Guard and Scouting Legion keep eliminating the Titans trapped inside Trost. Thanks to the cannons and Scouting Legion's prowess, the area of Trost becomes free of Titans after a whole day of fighting. Not only that, but two Titans are also captured alive. However, while mankind finally manages to win against the Titans, the price paid in exchange is far too high as a lot of soldiers have died or are injured.

Having to deal with the aftermath of the battle, Jean is then seen going through the corpses. Much to his shock, he then witnesses a corpse of Marco. Unable to believe this, he questions what happened. However, he is then approached by a medic who asks Jean for the deceased's name. After hearing that they're still collecting corpses in order to avoid an epidemic and knowing the names is helpful, Jean tells her Marco's name and his position as a soldier. Elsewhere, Sasha witnesses a lot of corpses as well. Questioning this, she is told by a soldier, much to her disbelief, that they're corpses that were thrown up by a Titan. At the same time, Annie is also looking at a corpse of a soldier, apologizing to them. Reiner, however, tells her that an apology won't fix it so they should just put them to rest.

At an unknown place, Eren suddenly wakes up and sees Erwin and Levi of the Scouting Legion. After being told that he is in an underground jail cell, being in the custody of the Military Police, Eren notices that Erwin is holding a key to the basement of his former house. Stating that he will give it back to Eren later, Erwin tries to confirm whether the basement holds the secrets of Titans, to which Eren replies that it's what his father said. Not trusting him, Levi states that it's convenient for Eren to have amnesia while his dad is missing, but Erwin insists that Eren has no reason to lie. They then ask Eren about what he wants to do and after recalling his past, he states that he wants to join the Scouting Legion in order to slaughter as many Titans as possible. This catches Levi's interest as he walks forward and says that he will take care of Eren, not because he trusts him, but because he can kill him if Eren betrays them. He then tells Eren that he will accept his application to the Scouting Legion.