The Colossal Titan is the largest of the Nine Titans at a staggering 60 meters tall, towering over every other Titan and all man-made structures. Its sheer size allows it to see over the Walls and destroy massive fortifications with a single kick. The Colossal Titan has no skin on its body, leaving exposed muscle and bone tissue visible across its entire form. Bertholdt Hoover used it to breach both Wall Maria and Wall Rose, while Armin Arlert later inherited it to defend Paradis.
The Colossal Titan has a gaunt, skeletal face with small sunken eyes and no visible nose or lips, giving it a haunting skull-like appearance. Its entire body lacks skin, revealing tightly wrapped muscle fibers and tendons over a massive skeletal frame. Steam constantly emanates from every surface of its body, creating an intimidating aura that obscures its form in battle. The neck and shoulders are particularly wide, and its legs are thickly muscled to support the enormous weight of the Titan body.
The Colossal Titan can release devastating steam explosions from its entire body, burning anything within a wide radius and pushing enemies back with tremendous force. It can control the size and power of its transformation, from a small localized blast to a city-destroying nuclear-level explosion. Its immense height gives it an unrivaled field of vision on the battlefield, and its body heat is so intense that anyone standing too close will suffer severe burns. After transforming, the Colossal Titan can sustain steam release for extended periods, though this gradually consumes its own muscle mass. The user can also detach portions of their Titan flesh in controlled explosions, creating targeted blasts without fully transforming.
Bertholdt Hoover was the original Colossal Titan warrior from Marley, responsible for the catastrophic breach of Wall Maria in 845. He maintained the Titan for years before passing it to Armin Arlert, who was chosen as Shiganshina's new hope. Arlin used the Colossal Titan's power in the final battle against Eren's Founding Titan, using a massive explosion to clear a path for his comrades.