Attack On Titan is a popular anime/manga series that follows the story of Eren Jaeger and his fight against humanoid man-eating monsters called Titans. After the end of the manga, fans can't wait to see the rest of the series animated. With the end of Attack On Titan near, it is important to rewatch the whole series in preparation for the final.

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With four seasons, it might be a lot for fans to binge in one sitting. It's important to know the episodes that are most important to the plot of Attack On Titan that mustn't be skipped. Although, almost every episode of Attack On Titan can be considered very important to the plot of the series.

10 The Very First Episode Is The Introduction To The Plot

AOT Eren and Mikasa Ep 1

To You, In 2000 Years: The Fall Of Shiganshina Part 1 is a must-watch as the first episode and introduction to the plot. Fans are introduced to a world where humanity is forced to hide behind three walls and protect themselves from the man-eating Titans. This protection doesn't last long. One day a Colossal Titan appears, breaks down a wall and causes chaos for all those living there. It is then that fans see Eren Jaeger's life fall apart right before their eyes.

9 The Colossal Titan Causes Choas Once Again

AOT Colossal Titan and Eren

After the traumatic experiences Eren faced, fans watch the training he took to become a Survey Crops member. In The Night Of The Closing Ceremony Part 2, fans get left on a cliffhanger of the Colossal Titan making its grand return. First Battle: Struggle For Trost, Part 1 shows Eren bravely trying to attack the Titan, but it disappears.

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Now Eren and the rest must take out the Titans breaching the wall to protect the townspeople. In an attempt to save his best friend from a Titan, Eren sacrifices himself and ends up getting eaten by the Titan.

8 Eren Is Revealed To Be A Titan Shifter In I Can Hear His Heartbreak

AOT Eren's Titan Form

After Eren's supposed death in First Battle: The Struggle For Trost, a Mysterious Titan appears in the next few episodes and saves Mikasa from a near-death experience. This Mysterious Titan goes on to kill the remaining Titans that have breached the wall and collapses due to the exhaustion. From the nape of the exhausted Titan emerges an unconscious Eren, this moment is important to the plot of Attack On Titan as it was the first reveal that humans are able to transform into Titans.

7 In Smile: Assault On Stohess, Annie Is Exposed As A Titan Shifter

AOT Female Titan

With the new knowledge of Titan Shifter's, thanks to Eren's miraculous transformation into a Titan, the Scouts start to theorize that the other Abnormal Titans could be traitors among them. Soon enough, in Smile: Assault On Stohess, Eren, Mikasa, and Armin try to lure Annie into a tunnel in an attempt to capture her as she is suspected to be the Female Titan. However, Annie catches onto their plan and transforms into her Titan form, ultimately proving their theory to be correct.

6 Beast Titan Introduces Fans To A New Titan

AOT Beast Titan

Beast Titan introduces fans to a brand new Titan unlike any other that has been seen before. Otherwise known as the Beast Titan, this Titan resembles a giant hairy beast. Beast Titan is intelligent enough to speak - something no Titan has ever done before. Beast Titan is a must-watch for fans since it's the introduction of a new character who proves to be a big obstacle for the Scouts throughout Attack On Titan.

5 Soldier Reveals Another Character As A Titan

AOT Ymir Titan Form

Throughout season 2, characters that were less of a focus in season 1 now getting their spotlight. This includes the relationship between the characters Ymir and Christa, which fans didn't get to see much of in the previous season.

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Especially in Soldier, when some of the Scouts are trapped in a castle surrounded by Titans. Soldier sees Ymir make the bold decision to reveal herself as a Titan Shifter. Ymir jumps out of the castle and turns into a Titan in an attempt to save Christa and the rest.

4 The Plot Twist In Warrior Can't Be Skipped Whatsoever

AOT Renier and Bertholdt Transformation

Once the Scouts return to the top Wall Rose, Reiner and Bertholdt pull Eren aside to reveal something that had fans completely shocked. Reiner tells Eren that he and Berholdt are the Coloasssal and Armored Titans. In Warrior, Eren refuses to believe him but Reiner uses his Titan power to heal a wound. After eavesdropping on their conversation, Mikasa takes action by attacking the newfound traitors. Unfortunately, they manage to transform before she can finish them off. Eren then transforms as well to battle the betrayers.

3 Eren Discovers A New Found Titan Power In Scream

AOT Eren Punches Titan

After losing the battle between the Colossal and Armored Titans, Eren gets kidnapped and the Scouts spend the next few episodes trying to rescue him. Once successfully rescued, Renier refuses to let him escape, so Eren starts launching Titans at the group of Scouts. In Scream, the Scouts are completely surrounded with no hope left, and things aren't looking good. Until, Eren suddenly unleashes a new power. In a desperate attempt to survive, Eren punches a Titan - causing other Titans to swarm the one Eren punched.

2 A Very Important Decision Needs To Be Made In Midnight Sun

AOT Armin Becomes A Titan Shifter

Season 3 shows the battle to retake Wall Maria, and Armin and Erwin get severely injured. The pair are basically on the brink of death but Eren successfully captures Bertholdt. Unfortunately, they can only save one of them by turning them into a Titan Shifter.

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Thus the fighting begins on who to save. Eren and Mikasa fight to save their best friend Armin while Levi wants to save commander Erwin. In the end of Midnight Sun, as Levi is about to save Erwin, he has a change of heart and decides to save Armin instead.

1 In Season 3, The Scouts Finally Make It To The Basement

AOT Scouts Find The Basement

One of the main goals of retaking Wall Maria was to find Eren's father's basement in hopes of learning more about Titan Shifters. In The Basement, fans finally see the Scouts uncover the secrets in Eren's father's basement. Once, they find three journals detailing Eren's father's life before the walls. This is a moment fans have been waiting to see since season 1 and definitely cannot be skipped.

NEXT: Attack On Titan: 10 Darkest Points In The Story, Ranked