The Colossal Titan, as its name implies, is the largest and most powerful Titan glimpsed thus far in the series. It is the entity responsible for the destruction of Eren and Mikasa's home district, as well as marking a turning point in the war between humans and Titans. Up until its appearance, humanity had been relatively safe behind the massive walls they erected, but the Colossal Titan is able to break through these and allow its smaller brethren in. It is the closest thing to being a primary antagonist for the series.
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