Colossal Titan

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 bwtween 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.

Biography
The Colossal Titan appears in Chapter 1, shortly after the history of the world and humanity's situation have been introduced, along with Mikasa, Eren and Armin. Its mere presence is enough to cause considerable panic amongst the population, as it is tall enough to see completely over the wall that is supposed to keep all Titans out. Within moments of its appearance, it attacks, repeatedly kicking the wall gates to the point that they rupture and open a hole large enough for other Titans to pass through. It then disappears after causing considerable structural damage to the wall, but does not attempt to participate in any meaningful way in the ensuing masscare itself.

It reappears five years later, again breaking through the walls so that