What Should I Do Now?

is the 5th and final chapter of the 4th volume and the 18th chapter overall of the Attack on Titan manga, written and illustrated by Hajime Isayama.
== Overview ==
In the final steps of their graduation, Armin struggles with a weighted march through rain under the instructor's supervision. Reiner takes Armin's pack to help him out, but Armin chooses to carry his own weight. The instructor notices this brief exchange, noting the strengths and weaknesses of the trainees before him. This continues into later vertical maneuvering equipment training in the forest. Afterward, the trainees begin discussing their results while they rest. Eren notes Marco's behavior during the test, stating that he would make a great leader with the skills and qualities he possesses. After the others leave, Marco turns to Jean to speak his mind.
Sometime later, two days after the sealing of the breach in Trost District, Jean finds Marco's corpse. After a moment of shock, he gives his name and listing to a . Elsewhere in the city, Sasha comes across Titan vomit, and Annie is apologizing to the corpses of the soldiers around her. Afterward, during the burning of the dead, Jean recalls Marco's words to him about his ability to be a truly good leader. Jean turns to the others, saying he wishes to join the Survey Corps.
Three days after the sealing of the Wall, Erwin Smith and Captain Levi explain to Eren of the events that happened during his coma. Erwin states that they could use Eren's Titan powers to seal the breach in Wall Maria as well. Eren says that he simply wants to kill Titans, which impresses Levi. Levi agrees to act as Eren's supervisor, welcoming him to the Survey Corps.
== Summary ==
During a march, Armin is having a hard time keeping up with his fellow trainees due to the weight of his pack. Reiner comes up behind him and takes his pack for him, but Armin quickly takes his pack back, choosing to carry his own weight rather than letting others bear his burdens. The instructor notices this exchange. Looking to Reiner Braun, he notes his great strength and willpower. He then turns to Armin, noting his lack of physical strength but exceptional skill in strategy.
In the forest, the trainees are being tested on their ability to use their vertical maneuvering equipment by attacking and "killing" wooden cutouts of Titans while the instructor notes their various strengths and weaknesses. Annie Leonhart shows great precision, but acts as a lone wolf of sorts. Bertolt Hoover has mastered his training and has much potential, but lacks the drive to make decisions. Jean Kirstein, who at the time is struggling to find a kill, is noted for his excellent maneuvering skills and quick decision-making, as well as his regrettable aggressive personality. As Jean finds a Titan prop, Connie Springer comes in to steal the kill. The instructor notes Connie's skill in maneuvering and balance, as well as his slow wit and strategic shortcomings. Ultimately, Sasha Blouse lands the first blow before either can get to the Titan. The instructor comments on her speed and remarkable instincts, as well as her conflict in situations involving organization. Elsewhere, Mikasa Ackerman and Eren Yeager are finding their own kills. Mikasa is noted for her historically unprecedented mastery of all skills required of her, while Eren is noted for his hand-to-hand skill and strong sense of purpose.
Now back at camp, Jean complains about the targets stolen from him. Eren notices that Marco barely attacked the targets. He explains that he thinks of a real-life situation, using himself as a decoy while others make the killing blow. Eren says that he is a good leader, with Sasha and others agreeing. A comment from Jean nearly causes a fight between him and Eren. Fortunately, the others are able to defuse the situation. When no one else is around, Marco stays behind with Jean to speak his mind.
Much later, two days after the sealing of the hole in Wall Rose, Jean is assigned to clean up dead bodies in Trost along with others. As he walks the ruined street, he looks over and sees the body of Marco, half-eaten by a Titan. Shocked, Jean tries to find anyone who knows about Marco's last moments. A nearby is taking the names of the dead, and asks Jean if he knows the body. He pays little attention, which causes the medic to say that right now their duty is to clean up the dead bodies before they contaminate the city. Jean, still at a loss, gives the medic Marco's name and listing.
In another part of the city, Sasha comes across a pile of partially eaten dead bodies. Not knowing what to make of it, a soldier from the Garrison tells her that Titans must not have intestinal tracts, since when they get full, they regurgitate. Annie sees a dead body and apologizes to it. Reiner, tells her that apologizing will not make any difference. In a hurry to get the memorial service over with, he thinks back to all the training they have gone through only to have this happen. At the memorial service, most of the remainder of the 104th Training Corps, stand in front of the funeral pyre. As Jean crouches, memories of Marco, Eren and others come to mind. He recalls the time when Marco spoke his mind to him. Back then, he said that Jean would make a great leader since he knew what it was like to be weak. He regrets joining the military only because he worries about which of his friends will be next. Announcing it to his friends nearby, he decides to enlist in the Survey Corps.
Three days after he sealed the breach, Eren wakes up from a coma caused by his last Titan transformation. Commander Erwin Smith and Captain Levi explain to him that it took a full day after the sealing of the breach to kill the remaining Titans with nonstop cannonfire, with two Titans being captured alive. Afterward, Eren realizes that he is locked in a cell underground. Commander Erwin begins to question him and shows him the key they found on his necklace. At the sight of the key, he is asked if it can give them the answers. Eren explains that if what his father said is true, then it will. Levi comments on the convenience of losing his memory at around the same time that his father goes missing, causing Erwin to correct him. Erwin then asks how he wants to go about getting to the basement. To do that they would have to recover Shiganshina District and plug the hole in Wall Maria, which unfortunately would prove to be a difficult task.
When Levi impatiently asks the same question, Eren, remembering his family and friends that have been killed, replies that he wants to kill all the Titans. Amused and somewhat impressed, Levi says that he will vouch for him to join their ranks, adding that if he shows a single sign of betrayal, Eren will be killed on the spot. With that, Captain Levi accepts Eren into the Survey Corps.
== Characters in order of appearance ==
== Navigation ==
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es:Capítulo 18
fr:Chapitre 18
it:Cosa si fa Adesso?
ru:Глава 18