Annie Leonhart

Annie Leonhardt is the third primary antagonist of Attack on Titan and revealed to be Annie Leonhart. A 14-meter tall Titan with a previously unheard of feminine body structure, encountered during the expedition to Wall Maria. She possesses obvious intelligence, extensive knowledge of hand-to-hand combat, and the ability to selectively regenerate or harden parts of her body during battle. Leading numerous other Deviant Titans, she attacks the expedition forces in search of Eren and attempts to kidnap him. She slaughters the forces sent to fight her, with only Levi, Mikasa, and Armin surviving direct contact with her.

It's possible that she, possibly along with Reiner Braun and Bertolt Hoover as well as people from her homeland, know more about true nature of titans, but unwilling to let Survey Corps know them as she killed Sonny and Bean, 2 captured titans.

History
It is speculated by Armin Arlert that Annie, in her Titan form, participated in the attack on Shiganshina District, possibly leading the Titans towards Wall Maria after the Colossal Titan first breached it, though this is never confirmed. Later, after the destruction of Shiganshina and subsequent loss of Wall Maria, young Annie is among the refugees to receive her food rations.

Annie later appears as an upcoming member of the 104th Trainees Squad, watching other trainees to be undergoing Keith Shadis' "rite of passage". However, the instructor doesn't speak a word to Annie and many others as their faces prove that they've already been through hell on Earth, according to another instructor.[15] Two years after that, during the trainees' training of hand-to-hand combat, Annie is seen sneaking away, with Reiner confronting her for that. He has Eren to face Annie, much to her apparent anger. However, the latter effortlessly takes the former down and Reiner soon follows him, ending up on the ground as well. Eren praises Annie for her technique and even though she reveals it was her father to teach her the move, as Eren shows interest, she dismisses the thought and claims such training to be useless and continues mocking the entire military system and even her father's ideals. Annie later watches as Eren uses her move to pacify Jean. She then expresses the will to teach Eren the proper way to perform it.[16] Annie continues her training until she successfully graduates at the rank of four.

Battle of Trost Disctrict
Shortly after the graduation, the Colossal Titan appears in Trost District and breaks through the outer gate, letting Titans into the town. In spite of the evacuation being finished, the trainees are unable to return due to insufficient gas, much to everyone's despair. In this situation, Annie is suddenly approached by Mikasa, looking for Eren. She is then surprised to hear that he, along with most of his squad, were supposedly killed in a battle. Trying to keep her cool, Mikasa attempts to shock everyone into action, with Annie and others rushing after her to reach the HQ and replenish their gas. They eventually manage to get there, albeit with casualties.

With the mysterious Rogue Titan fending off most of the Titans attacking the HQ, Annie and others attempt to get rid of the small Titans inside. After the plan's success, the group witnesses the Rouge Titan being eaten by other Titans. Annie overhears Jean and Reiner arguing about whether to take an action or not and proclaims that the Rogue Titan should be kept alive as it might serve as a powerful ally. At this point, she learns about Eren's Titan Shifting ability after Eren emerges from the nape of the Rogue Titan's neck.

Unbeknownst to the rest of the soldiers, Eren ends up being questioned and eventually attempted to be killed by Kitts Woerman due to his Titan ability. Annie and the rest overhear the lightning strike that is caused by Eren's second, albeit half-formed, transformation into his Rogue Titan form to defend Mikasa and Armin from cannon fire. This alarms Reiner enough for him to rush near the vicinity of the lightning strike with Jean, Annie and Bertolt quickly following suit, at which point they witness the scene of Eren's Titan form surrounded by soldiers of the Stationary Guard. They watch as Armin attempts to persuade the soldiers that Eren is strategically important for mankind until Dot Pixis arrives and stops Woerman. In the aftermath of the Battle of Trost, Annie is seen apologizing to an unknown corpse as she, Reiner, and Bertolt assist in cleaning up the remaining corpses of other soldiers. Later, as they watch the burning corpses, Annie and others are asked by Jean about their choice of the military branch they want to join as he exclaims that he will enlist into the Survey Corps.

The Female Titan arc
Soon after Eren's enlistment into the Survey Corps, the two Titans captured for research, Sonny and Bean, are killed and the Military Police Brigade  check the Three Dimensional Maneuver Gears of the trainees. During this time, Armin, Annie and Connie Springer discuss which military branch they want to join. When Annie reveals that she will go to the Military Police Brigade, Connie considers joining them too and asks for her opinion. Annie responds telling him that it's his decision to make, not hers. When she learns Armin plans to join the Survey Corps, she asks him what he would do if he was ordered to die. He tells her if the reasons are good, then he'll do so. Annie thinks he's weak physically, but yet he's very strong at heart. Though Annie had offered Marco Bott's 3DMG for inspection as her own, unbeknownst to her this prompts Armin to become suspicious of her. Ultimately during the Survey Corps draft, Annie leaves to join the Military Police.

During the 57th Expedition of the Survey Corps, Annie makes her first appearance in her Female Titan form as she leads a group of Titans to capture Eren, wiping out the majority of the scouts on the right side of the Survey Corps' formation. Advancing further inside the formation, Annie encounters Armin. Although she corners Armin, recognizing his face under the hood she decides to spare his life and continues her search for Eren. Armin, Jean and Reiner join together and deduce that she aims to capture Eren, realizing that Annie may have acted upon false information as part of Erwin's plan. The three are able to deduce that it is more likely for Eren to be within the center column; the safest location in the formation.

Armin, Jean and Reiner coordinate a plan together in an attempt to distract Annie to buy the other soldiers some time to regroup, but before they are able to attack her, she is able to outmaneuver them in which she manages to incapacitate Armin. Although Jean engages her in combat, her resilience and awareness of a Titan's weakness allows her to gain the advantage as she is constantly covering the nape of her Titan form's neck. Before Annie is able to kill Jean, a bloodied Armin attempts to distract her by referring to Eren by the nickname of "suicidal bastard" while falsely claiming his death. This causes Annie to halt her movements in state of hesitation and confusion, allowing Jean the time to escape just as Reiner attempts to attack her. Annie manages to catch Reiner in mid-air, briefly toying with him before seemingly crushing him. Much to Jean and Armin's surprise, Reiner breaks free by slicing off her fingers, and manages to come to Armin's aid leaving Annie as she sits motionless. Just as the trio attempts to flee, Annie begins to head in the direction of the Survey Corps' center column formation, in which Armin deduced that Annie may have learned of Eren's position in the formation. Annie continues to head in the direction of Eren's location, coming across various soldiers of the Survey Corps, killing them in various brutal ways. Though the formation heads into the Forest of Giant Trees, Annie follows suit and eventually catches up to Eren and the Special Operations Squad as they are attempting to flee on horseback.

Annie is eventually lured into a trap in which her movements are halted by artillery fire armed with harpoons. This causes Annie to temporarily halt her pursuit as Erwin and members of the Survey Corps attempt to damage her hands in various ways with the intention of pulling her out of her Titan form. Constant provocations by Levi causes her to let out a roar which causes multiple Titans to converge on her position. Much to Erwin's surprise, the roar was intended to provoke the Titans to devour her Female Titan form, thus causing Annie to escape from her Titan form undetected via use of her 3D Maneuver Gear. Just as Erwin orders all personnel to retreat, Annie later dons a Survey Corps cloak as a form of disguise, signaling a green flare so as to lure Eren and the Special Operations Squad towards her direction.

As Annie meets up with the group, she is mistaken for Levi though not for long, as Gunther questions her identity. Annie makes quick work of Gunther, killing him using her blades. As Eren and the Special Operations Squad continue to flee, Annie transforms into the Female Titan for a second time, thus continuing her pursuit to capture Eren. Although Eren initially wishes to engage her in his Rogue Titan form, the Special Operations Squad manage to convince him to put his faith in them as they begin to engage Annie in combat. Although seemingly gaining the advantage to the point of injuring her and cornering her onto a tree, the Special Operations Squad are suddenly outsmarted by Annie as she displays her ability of selective regeneration and her ability to generate a crystalline substance to protect her nape. Annie systematically kills Eld, Petra and Oluo, causing Eren to turn back and finally engage her in his Rogue Titan form. The two engage in a brutal fight using hand-to-hand combat techniques, in which Annie succeeds in incapacitating Eren's Rogue Titan form with her signature kick. Tired and exhausted from the battle, Eren is captured by Annie by keeping him inside the mouth of her Female Titan form. Although Annie begins to flee, Mikasa gives chase while continuously attacking her in a fit of rage after having witnessed Eren's capture by Annie's Female Titan form.

Mikasa is then joined by Levi, with the two working together to wound Annie as she continues to flee. Although Annie attempts to fight back, she begins to get overwhelmed by the barrage of attacks inflicted by the two, allowing Levi to incapacitate her while gaining the chance to slice her Titan form's mouth and rescue Eren from within. As Mikasa and Levi decide to retreat with the unconscious Eren, Levi witnesses Annie's Female Titan form as it sits motionless while crying. Some time later, Annie awakens in her room in the Stohess District of Wall Sina. Her hair is depicted as having the same appearance as the Female Titan's when not tied up in a bun. Upon arrival with other rookie members of the Military Police Brigade, Annie is teased by Hitch and Marlo Sand, but Boris Feulner tells them to leave her alone believing that she hasn't recovered from battle and is the only one who has real combat experience. The group is then given an assignment in which they are to guard a Survey Corps convoy with permission to use their 3D Maneuver Gear. Soon after departing for her assignment, Armin approaches her and asks for help in hiding Eren until they can convince the king to better protect the walls. Annie reluctantly agrees whilst putting on a ring and escorts them to a place where they can hide.

When Eren and Armin attempt to convince her to join them in an underground passageway, she refuses for supposedly feeling frightened, all while expressing her suspicion towards their plan. As Eren and Armin continue to plea for Annie to join them and prove herself innocent, Mikasa, growing tired of their discussion, takes off her hood and draws out her blades while revealing her 3D Maneuver Gear. She openly refers to Annie as the Female Titan, taunting her to fight just as two had fought before. Their suspicion is confirmed when Annie noticeably smiles in relief and acceptance of their discovery of her identity as the Female Titan; further proven by her refusal to enter the passage, where she cannot transform. Annie praises Armin's efforts for betting on his plan, declaring afterwards that her gamble has only just begun. After Armin fires a signal, disguised Survey Corps members come out of their hiding places, and restrain Annie. Seemingly captured and immobile, she still manages to flick her thumb to open a small blade hidden in her ring and wound herself, thereby allowing her to transform into her Female Titan form; thus killing those restraining her in the process. Now, resuming her attempts to capture Eren, Armin and Mikasa realize how desperate she is, and try to get him to fight her. Overcoming his initial hesitation, Eren transforms into his Rogue Titan form and takes Annie on in her Female Titan form.

Annie takes flight towards the wall soon after Eren transforms. She is pursued by him, Mikasa and several Survey Corps squads. The chase continues until Annie reaches a flat land with no buildings. Having nowhere to hook their 3D Maneuver Gear anchors, the Survey Corps squads and Mikasa are forced to take a long detour, while Eren gives chase alone. Annie uses this opportunity for one last ditch attempt at capturing Eren, a brief struggle between the two of them ensues, but she fails again. After that, she continues to try and escape by scaling the wall.



Armin, upon realizing that catching up with her by using 3D Maneuver Gear would be impossible, instructs Titan Eren to throw Mikasa upward, towards Annie. His plan works and Mikasa reaches Annie moments before she is about to reach the top of the wall. Not hesitating in the slightest, she cuts off all of the fingers of Annie's Female Titan form, leaving her struggling to hold on. Mikasa then tells her to fall down and pushes her off via the head. Eren, in his Titan form, holds down the body as both the soldiers, cut into the flesh and try to extract Annie. Upon extracting Annie from the Titan body, they find out Annie is completely enclosed inside a presumably indestructible crystal.