If one were to ask Attack on Titan fans about their favorite character, most would probably reply Levi, Eren, or Mikasa. The mere presence of these memorable characters alters the course of the Eldian-Marleyan war, and in Eren's case, even the face of the planet.

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But some would remember Commander Erwin Smith's contribution to humanity's struggle, his genius, his charisma, and his complexity as a character. Even among a cast of intense, strong-willed characters, Erwin stands out, and his final stand against the Beast Titan remains one of the most touching scenes of the anime. But despite his brilliance, Erwin has had his own fair share of failures.

10 His Childhood Recklessness Is What Leads To His Father's Death

Young Erwin at his father's grave Attack on Titan

When Erwin is a child, he asks a question in his father's class. His father doesn't immediately answer, but in private, he explains he has a theory-- that the king altered his subjects' memories. Erwin recklessly shares the information with other children. When the Military Police hear about it, they have Erwin's father killed. Erwin realizes that his father's theory must have been at least in part correct and dedicates his life to atoning for his foolishness.

9 He Gives Up The Woman He Loves To His Friend Nile

Nile Dok pointing gun at Erwin Attack on Titan

In order to achieve his dream, Erwin joins the Training Corps as soon as he is old enough. He and his friend Nile Dok both plan on joining the Survey Corps together in the hope of starting a real quest for answers. The two men meet a woman named Marie, and both fall in love with her.

Erwin chooses to give her up, but Nile abandons their plans and joins the Military Police instead. Nile originally advocates for Eren's execution when Eren's Titan powers are revealed and even arrests Erwin. He changes his mind when the government's corruption is revealed. He and Marie have three children, and he is among the officials doomed by drinking Zeke's poisoned wine.

8 His Genius Stratagems Are Originally Rejected By The Commander Of The Survey Corps

Keith Shadis From Attack on Titan

After joining the Survey Corps, Erwin gradually climbs up the ranks. When a Survey Corps base is overrun by titans, Erwin approaches Commander Keith Shadis with a genius stratagem, one that would allow the scouts to fight more safely. In his arrogance, Keith rejects the idea. It's a failure on Erwin's part, even if only a temporary one.

7 He Becomes A Demon To Achieve His Own Selfish Goals

Erwin Mountain of Corpses AOT

Following one too many failures, Commander Keith Shadis realizes Erwin is superior to him. Plagued by guilt at his mistakes, he passes the leadership of the Survey Corps onto Erwin. The decision is a good one, as Erwin is far more successful in his missions than Shadis ever was. Even so, Erwin still sacrifices his subordinates, all in the hope of proving his father right. He also wishes to find answers about the titans, about what they really are. While everyone else fights to protect humanity, he fights for a selfish reason. His actions haunt him up to the day of his death.

6 The Plan To Capture The Female Titan In The Forest Is A Failure

Scouts trap the Female Titan with wires in the forest

One of the primary antagonists in the first part of the anime, the Female Titan is perhaps the most versatile fighter among the Nine Titans. Fast and strong, she also possesses the ability to summon other titans with a scream. Its inheritor, Annie Leonhart, uses this power to provide reinforcements for the Colossal Titan and Armored Titan during the invasion of the Shiganshina District. Erwin and the rest of the Survey Corps are aware of how dangerous she is.

RELATED: Attack On Titan: 10 Things You Need To Know About The Female Titan

Together with Levi, Erwin hatches a plan to capture her in the Titan Forest. At first, the plan does seem to work. Using the special target restraining weapon, they are able to immobilize the Female Titan. She summons other titans with a scream, and they devour the titan body, giving Annie herself the chance to make her escape. Throughout the expedition, she is able to transform for a second time, killing many members of Levi's team. She also defeats Eren's Attack Titan and would have captured him if not for Levi and Mikasa's intervention.

5 The Ambush On Annie In The Stohess District Results In A Great Deal of Destruction

Female Titan blocking a punch AOT

After the scouts realize Annie is most likely the Female Titan, Erwin comes up with a plan to ambush her in the Stohess District. They are in part successful, in that Annie does reveal herself. But in many other ways, the ambush doesn't go well. The ensuing battle between Annie's Female Titan and Eren's Attack Titan results in a great deal of destruction. Not only that, but upon being defeated, Annie encases herself in a shell of crystal, keeping the scouts from getting answers from her.

4 Erwin Loses An Arm While Trying To Rescue The Kidnapped Eren

Erwin From Attack on Titan with an injured arm

After Eren is kidnapped by Reiner and Bertholdt, Erwin quickly organizes an operation to track them down and rescue him. In the ensuing battle, a titan leaps out at him, grabs him off his horse, and tears off his arm. He tells his soldiers to advance even as the titan is chewing on his arm, and the group recovers Eren, even if it costs them more lives. Erwin falls into a temporary coma due to the loss of his limb. He seems at peace with it, but he also acknowledges that it's a loss that makes him a less capable soldier.

3 During The Battle Of Shiganshina District, He And His Subordinates Are Trapped By The Beast Titan

Levi-Erwin-Attack-on-Titan

The Battle of Shiganshina District is a huge turning point in Attack on Titan. Aware that the answers he wants so badly are most likely hidden in Eren's basement, Erwin leads a large team of over one hundred Scouts into Shiganshina. Reiner, Bertholdt, and Zeke are lying in wait.

Zeke traps the Survey Corps using a titan army, taking them completely by surprise. Meanwhile, Reiner and Bertholdt strike the Scouts from the opposing side. The Colossal Titan's transformation does massive damage to their forces, and Hange Zoe's squad is almost completely killed. In the end, Erwin finds himself with no way out. Left with no avenue of escape, he and his subordinates are showered with massive chunks of rock thrown by the Beast Titan.

2 His Final Gamble, While Genius, Doesn't Accomplish Its Purpose

Erwin's suicide charge against Beast titan AOT

Acknowledging his desperate circumstances, Erwin comes up with one last gamble. In the final operation of Erwin's Scouts, they embark on a suicidal charge that has a single purpose--to give Levi the chance to approach the Beast Titan and assassinate him.

RELATED: Attack On Titan: The Eldians' 10 Biggest Failures, Ranked

The brilliant plan is almost successful, and Levi does indeed reach Zeke and take him down. But Zeke is rescued at the last moment by Pieck in her Cart Titan form, so Erwin's sacrifice amounts to nothing.

1 He Dies Without Ever Knowing What Is Inside The Basement

Erwin on his death bed AOT

Despite dedicating his life to figuring out the truth, despite being convinced the answers are in Eren's basement, Erwin dies before he can ever reveal Grisha Yeager's hidden secrets. His biggest sacrifice is going to his death with the full knowledge that this was going to happen, and that his life's work has primarily been for nothing.

NEXT: Attack On Titan: 10 Characters Who Survived The Series (But Shouldn't Have)