TV-Series
Description
Armin Arlert is a central figure in the final season, having evolved from a timid and physically weak child into the strategic lynchpin of the Survey Corps and the inheritor of the Colossal Titan. By the time of the final chapters, he is nineteen years old and stands as the 15th commander of the Survey Corps, having taken on the role after the death of Hange Zoe.

Growing up in the Shiganshina District, Armin was frequently bullied and relied on his childhood friends, Eren Yeager and Mikasa Ackerman, for protection. His defining characteristic from a young age was an intense curiosity about the outside world, fueled by a forbidden book belonging to his grandfather that described oceans, burning ice, and vast deserts. This dream of discovering what lay beyond the walls was the foundation of his bond with Eren and remained his primary motivation for years.

In terms of personality, Armin is defined by a unique combination of profound empathy and exceptional intelligence. While he possesses a genius-level strategic mind, rated at the highest level by his instructors, he is not naturally aggressive or confident. He has a long history of self-doubt, often feeling like a burden to his stronger friends. However, throughout the series, and especially in the final season, he overcomes this to become a decisive leader. He retains his deeply humanistic worldview, always striving to understand the enemy and find a peaceful resolution, even when faced with overwhelming violence. He is capable of feeling immense guilt and remorse for the lives he has taken, such as during the raid on Liberio, but understands that such actions are sometimes necessary.

Armin's primary motivation shifts over the course of the final season. Initially, his goal is to see the ocean, a milestone he and his friends achieve. After that, his purpose becomes the protection of Paradis and, more importantly, saving his childhood friend Eren from himself. He refuses to accept Eren's genocidal plan, the Rumbling, as inevitable. Instead, Armin is driven by the belief that humanity can find another way, embodying the role of someone who can imagine a future beyond endless cycles of hatred. He is not the hero of the battle, but the hero of the story that comes after the conflict, tasked with guiding the survivors towards peace.

Armin's role in the final chapters is multifaceted. He is the primary strategist for the Alliance, a group composed of former enemies from Paradis and Marley who unite to stop the Rumbling. He succeeds Hange as commander and is the bearer of the Colossal Titan, a power of mass destruction he uses reluctantly but effectively, such as when he destroyed the Marleyan fleet at Liberio and later when he confronted Eren's Founding Titan form. His most critical role, however, is as a diplomat and moral compass. He confronts Eren in the Paths dimension, a metaphysical space, and engages in a final conversation that seeks to understand his friend's pain rather than simply condemn his actions. In this moment, Armin demonstrates his core strength: the ability to find a shred of humanity and beauty, symbolized by a seashell, even within a hellish landscape of destruction.

Key relationships define his journey. His bond with Eren is the most complex; they share a dream, but Armin is forced to become Eren's adversary to stop the Rumbling, all while still loving him as a friend. His relationship with Mikasa remains one of unwavering mutual support. Additionally, his connection with Annie Leonhart deepens in the final season; he visits her crystallized form for four years, speaking to her and fostering a unique understanding that eventually leads to a close bond.

Armin's development from the final season's beginning to its end is significant. He transitions from a soldier grappling with survivor's guilt over being chosen to live instead of Commander Erwin Smith, to a confident commander making impossible choices. He moves from simply following orders to leading a coalition of former enemies. By the conclusion, he has fully grown into the potential his friends always saw in him, becoming the individual who carries the burden of explaining the past and advocating for a peaceful future, effectively inheriting Eren's will to explore the world.

Regarding his notable abilities, Armin is not a physical powerhouse. His combat skills are rated low, and his true strength lies in his intellect, which has been compared to that of a general or a scholar. His strategic planning is consistently shown to be superior to his peers, allowing him to outmaneuver enemies like the Female Titan and the Colossal Titan before inheriting its power. As the Colossal Titan, he stands sixty meters tall and can produce an explosive transformation capable of leveling a harbor, as well as emit superheated steam for defense and attack. However, his most notable ability is ultimately his unbreakable imagination and his capacity for empathy, which allows him to see past the horrors of war to the people caught within it.